Need help diagnosing extremely slow boot, kernel i/o errors

I can't pinpoint the start of my problems to any known event, but about two weeks ago, my MacBook Pro started taking six to eight minutes to boot, and it hangs every time I mouse over or click "help" in the file menu.

I've run hardware test and disk repair and fsck -fy and run all around trying to get this worked out, but nothing has helped.

Not being a hardcore user, it took me a while to find the Console log of the startup, but it seems that there's ongoing i/o errors that are delaying the startup. Anybody have any ideas?

Here's the log:

Jan 25 12:18:49 localhost com.apple.launchctl.System[2]: launchctl: Please convert the following to launchd: /etc/mach_init.d/dashboardadvisoryd.plist
Jan 25 12:18:50 localhost com.apple.launchd[1] (com.adobe.versioncueCS3): Unknown key: ServiceDescription
Jan 25 12:18:50 localhost com.apple.launchd[1] (com.apple.blued): Unknown key for boolean: EnableTransactions
Jan 25 12:18:50 localhost com.apple.launchd[1] (org.cups.cupsd): Unknown key: SHAuthorizationRight
Jan 25 12:18:50 localhost com.apple.launchd[1] (org.ntp.ntpd): Unknown key: SHAuthorizationRight
Jan 25 12:18:51 localhost kernel[0]: npvhash=4095
Jan 25 12:18:50 localhost kextd[10]: 428 cached, 0 uncached personalities to catalog
Jan 25 12:18:51 localhost kernel[0]: hi mem tramps at 0xffe00000
Jan 25 12:18:51 localhost kernel[0]: PAE enabled
Jan 25 12:18:51 localhost kernel[0]: 64 bit mode enabled
Jan 25 12:18:51 localhost kernel[0]: Darwin Kernel Version 9.6.0: Mon Nov 24 17:37:00 PST 2008; root:xnu-1228.9.59~1/RELEASE_I386
Jan 25 12:18:51 localhost kernel[0]: standard timeslicing quantum is 10000 us
Jan 25 12:18:51 localhost kernel[0]: vm pagebootstrap: 771029 free pages and 15403 wired pages
Jan 25 12:18:51 localhost kernel[0]: mig table_maxdispl = 79
Jan 25 12:18:51 localhost kernel[0]: 105 prelinked modules
Jan 25 12:18:51 localhost kernel[0]: AppleACPICPU: ProcessorApicId=0 LocalApicId=0 Enabled
Jan 25 12:18:51 localhost kernel[0]: AppleACPICPU: ProcessorApicId=1 LocalApicId=1 Enabled
Jan 25 12:18:51 localhost kernel[0]: Loading security extension com.apple.security.TMSafetyNet
Jan 25 12:18:51 localhost kernel[0]: calling mpo policyinit for TMSafetyNet
Jan 25 12:18:51 localhost kernel[0]: Security policy loaded: Safety net for Time Machine (TMSafetyNet)
Jan 25 12:18:51 localhost kernel[0]: Loading security extension com.apple.nke.applicationfirewall
Jan 25 12:18:51 localhost kernel[0]: Loading security extension com.apple.security.seatbelt
Jan 25 12:18:51 localhost kernel[0]: calling mpo policyinit for mb
Jan 25 12:18:51 localhost kernel[0]: Seatbelt MACF policy initialized
Jan 25 12:18:51 localhost kernel[0]: Security policy loaded: Seatbelt Policy (mb)
Jan 25 12:18:51 localhost kernel[0]: Copyright (c) 1982, 1986, 1989, 1991, 1993
Jan 25 12:18:51 localhost kernel[0]: The Regents of the University of California. All rights reserved.
Jan 25 12:18:52 localhost kernel[0]: MAC Framework successfully initialized
Jan 25 12:18:52 localhost kernel[0]: using 15728 buffer headers and 4096 cluster IO buffer headers
Jan 25 12:18:52 localhost kernel[0]: IOAPIC: Version 0x20 Vectors 64:87
Jan 25 12:18:52 localhost kernel[0]: ACPI: System State [S0 S3 S4 S5] (S3)
Jan 25 12:18:52 localhost kernel[0]: mbinit: done
Jan 25 12:18:52 localhost kernel[0]: Security auditing service present
Jan 25 12:18:52 localhost kernel[0]: BSM auditing present
Jan 25 12:18:52 localhost kernel[0]: rooting via boot-uuid from /chosen: 6AC8E140-0895-369A-BF19-809377A519B1
Jan 25 12:18:52 localhost kernel[0]: Waiting on <dict ID="0"><key>IOProviderClass</key><string ID="1">IOResources</string><key>IOResourceMatch</key><string ID="2">boot-uuid-media</string></dict>
Jan 25 12:18:52 localhost kernel[0]: AppleYukon2: 532111ab,00000000 sk98osx_dnet - CheckDictionaryEntry failed, expected vs. dictionary
Jan 25 12:18:52 localhost kernel[0]: Got boot device = IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/SATA@1F,2/AppleAHCI/PRT2 @2/IOAHCIDevice@0/AppleAHCIDiskDriver/IOAHCIBlockStorageDevice/IOBlockStorageDri ver/SAMSUNG HM500LI Media/IOGUIDPartitionScheme/Apple HFS_Untitled1@2
Jan 25 12:18:52 localhost kernel[0]: BSD root: disk0s2, major 14, minor 2
Jan 25 12:18:52 localhost kernel[0]: FireWire (OHCI) TI ID 8025 built-in now active, GUID 0019e3fffe8db372; max speed s800.
Jan 25 12:18:52 localhost kernel[0]: [Bluetooth::CSRHIDTransition] switchToHCIMode (legacy)
Jan 25 12:18:52 localhost kernel[0]: [Bluetooth::CSRHIDTransition] transition complete.
Jan 25 12:18:52 localhost kernel[0]: [HCIController][configurePM] power parent ready after 1 tries
Jan 25 12:18:52 localhost kernel[0]: Jettisoning kernel linker.
Jan 25 12:18:52 localhost kernel[0]: Resetting IOCatalogue.
Jan 25 12:18:52 localhost kernel[0]: display: family specific matching fails
Jan 25 12:18:52 localhost kernel[0]: Matching service count = 0
Jan 25 12:18:52 localhost kernel[0]: Matching service count = 1
Jan 25 12:18:52: --- last message repeated 4 times ---
Jan 25 12:18:52 localhost kernel[0]: Previous Shutdown Cause: 5
Jan 25 12:18:52 localhost kernel[0]: AppleIntelCPUPowerManagement: initialization complete
Jan 25 12:18:52 localhost kernel[0]: display: family specific matching fails
Jan 25 12:18:52 localhost kernel[0]: ath_attach: devid 0x24
Jan 25 12:18:52 localhost kernel[0]: Override HT40 CTL Powers. EEPROM Version is 14.4, Device Type 5
Jan 25 12:18:52 localhost kernel[0]: mac 12.10 phy 8.1 radio 12.0
Jan 25 12:19:18 localhost kernel[0]: disk0s2: I/O error.
Jan 25 12:19:18 localhost kernel[0]:
Jan 25 12:19:19: --- last message repeated 1 time ---
Jan 25 12:19:19 localhost bootlog[37]: BOOT_TIME: 1232903926 0
Jan 25 12:19:20 localhost rpc.statd[19]: statd.notify - no notifications needed
Jan 25 12:19:21 localhost fseventsd[28]: bumping event counter to: 0x17ed122 (current 0x0) from log file '00000000017ecea0'
Jan 25 12:19:21 localhost DirectoryService[33]: Launched version 5.6 (v514.24)
Jan 25 12:19:21 localhost /System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow[24]: Login Window Application Started -- Threaded auth
Jan 25 12:19:22 localhost kernel[0]: yukon: Ethernet address 00:17:f2:d9:9b:0d
Jan 25 12:19:22 localhost kernel[0]: AirPort_Athr5424ab: Ethernet address 00:1b:63:02:ad:60
Jan 25 12:19:22 localhost blued[50]: Apple Bluetooth daemon started.
Jan 25 12:19:48 localhost kernel[0]: disk0s2: I/O error.
Jan 25 12:19:48 localhost kernel[0]:
Jan 25 12:19:48 localhost kextd[10]: writing kernel link data to /var/run/mach.sym
Jan 25 12:19:48 localhost kernel[0]:
Jan 25 12:19:50 localhost kernel[0]: AirPort: Link Down on en1
Jan 25 12:19:51 Macintosh-6 configd[35]: setting hostname to "Macintosh-6.local"
Jan 25 12:19:51 Macintosh-6 kernel[0]: AirPort: Link Up on en1
Jan 25 12:19:51 Macintosh-6 mDNSResponder mDNSResponder-176.3 (Sep 30 2008 16:59:38)[23]: starting
Jan 25 12:19:53 Macintosh-6 /usr/sbin/ocspd[68]: starting
Jan 25 12:19:53 Macintosh-6 com.apple.SystemStarter[17]: Starting RDUSB0074Setupd
Jan 25 12:19:54 Macintosh-6 Data Backup[76]: Starting Data Backup Executor Daemon
Jan 25 12:19:56 Macintosh-6 sandbox-compilerd[42]: bootstrap look_up_peruser slow answer, took 5.183063 seconds, shouldn't have taken more then 5
Jan 25 12:20:28 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:20:28 Macintosh-6 kernel[0]:
Jan 25 12:20:53: --- last message repeated 1 time ---
Jan 25 12:20:53 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:21:21 Macintosh-6 kernel[0]:
Jan 25 12:21:21: --- last message repeated 1 time ---
Jan 25 12:21:21 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:21:21 Macintosh-6 kernel[0]:
Jan 25 12:21:31: --- last message repeated 1 time ---
Jan 25 12:21:31 Macintosh-6 mds[22]: (Error) DiskStore: mdsStoreCheckin p:7683 qp:43779 kr:268451843 e:(ipc/rcv) timed out
Jan 25 12:21:51 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:21:51 Macintosh-6 kernel[0]:
Jan 25 12:22:14: --- last message repeated 1 time ---
Jan 25 12:21:51 Macintosh-6 mds[22]: (Error) Store: Store check-in failed: (ipc/send) invalid destination port
Jan 25 12:22:14 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:22:36 Macintosh-6 kernel[0]:
Jan 25 12:22:36: --- last message repeated 1 time ---
Jan 25 12:22:36 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:22:58 Macintosh-6 kernel[0]:
Jan 25 12:22:58: --- last message repeated 1 time ---
Jan 25 12:22:58 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:22:58 Macintosh-6 kernel[0]:
Jan 25 12:23:28: --- last message repeated 1 time ---
Jan 25 12:23:29 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:23:29 Macintosh-6 kernel[0]:
Jan 25 12:23:51: --- last message repeated 1 time ---
Jan 25 12:23:51 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:23:51 Macintosh-6 kernel[0]:
Jan 25 12:23:52: --- last message repeated 1 time ---
Jan 25 12:23:52 Macintosh-6 loginwindow[24]: Login Window Started Security Agent
Jan 25 12:24:51 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:24:51 Macintosh-6 kernel[0]:
Jan 25 12:25:18: --- last message repeated 1 time ---
Jan 25 12:25:18 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:25:18 Macintosh-6 kernel[0]:
Jan 25 12:25:42: --- last message repeated 1 time ---
Jan 25 12:25:42 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:25:42 Macintosh-6 kernel[0]:
Jan 25 12:26:00: --- last message repeated 1 time ---
Jan 25 12:26:00 Macintosh-6 authorizationhost[103]: MechanismInvoke 0x12f620 retainCount 2
Jan 25 12:26:00 Macintosh-6 SecurityAgent[104]: MechanismInvoke 0x101660 retainCount 1
Jan 25 12:26:01 Macintosh-6 SecurityAgent[104]: NSSecureTextFieldCell detected a field editor ((null)) that is not a NSTextView subclass designed to work with the cell. Ignoring...
Jan 25 12:26:01 Macintosh-6 loginwindow[24]: Login Window - Returned from Security Agent
Jan 25 12:26:01 Macintosh-6 SecurityAgent[104]: MechanismDestroy 0x101660 retainCount 1
Jan 25 12:26:01 Macintosh-6 authorizationhost[103]: MechanismDestroy 0x12f620 retainCount 2
Jan 25 12:26:01 Macintosh-6 loginwindow[24]: USER_PROCESS: 24 console
Jan 25 12:26:01 Macintosh-6 com.apple.launchd[1] (com.apple.UserEventAgent-LoginWindow[95]): Exited: Terminated
Jan 25 12:26:01 Macintosh-6 com.apple.launchctl.Aqua[179]: launchctl: Please convert the following to launchd: /etc/mach init_peruser.d/RemoteUI.plist
Jan 25 12:26:07 Macintosh-6 /System/Library/CoreServices/coreservicesd[49]: SFLSharePointsEntry::CreateDSRecord: dsCreateRecordAndOpen(Apple's Public Folder) returned -14135
Jan 25 12:26:07 Macintosh-6 /System/Library/CoreServices/coreservicesd[49]: SFLSharePointsEntry::CreateDSRecord: dsCreateRecordAndOpen(Isaac Guzman's Public Folder) returned -14135
Jan 25 12:26:07 Macintosh-6 /System/Library/CoreServices/coreservicesd[49]: SFLSharePointsEntry::CreateDSRecord: dsCreateRecordAndOpen(Old Ike's Public Folder) returned -14135
Jan 25 12:26:14 Macintosh-6 Finder[192]: [QL ERROR] Generator database update takes too long... we will use what we currently have
Jan 25 12:26:39 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:26:39 Macintosh-6 kernel[0]:
Jan 25 12:26:57: --- last message repeated 1 time ---
Jan 25 12:26:57 Macintosh-6 quicklookd[203]: [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest /Users/Old Ike/Documents/25 Best Career Moves Candidates 3.doc>'
Jan 25 12:26:59 Macintosh-6 /usr/sbin/ocspd[216]: starting
Jan 25 12:27:10 Macintosh-6 quicklookd[214]: [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest /Users/Old Ike/Documents/25 Best Career Moves Candidates 2.doc>'
Jan 25 12:27:27 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:27:27 Macintosh-6 kernel[0]:
Jan 25 12:27:42: --- last message repeated 1 time ---
Jan 25 12:27:42 Macintosh-6 quicklookd[217]: [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest /Users/Old Ike/Documents/25 Best Career Moves Candidates - First 12.doc>'
Jan 25 12:27:59 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:27:59 Macintosh-6 kernel[0]:
Jan 25 12:27:45 Macintosh-6 Dock[190]: [QL ERROR] Generator database update takes too long... we will use what we currently have
Jan 25 12:27:59 Macintosh-6 kernel[0]:
Jan 25 12:28:03 Macintosh-6 SystemUIServer[191]: SyncServer is unavailable: exception when connecting: connection timeout: did not receive reply
Jan 25 12:28:20 Macintosh-6 quicklookd[220]: [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest <a class="jive-link-external-small" href="file://">file://localhost/Users/Old%20Ike/Pictures/95%2012%20San%20Simeon %20Hearst%20Castle%20pool.tif>'
Jan 25 12:28:41 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:28:41 Macintosh-6 kernel[0]:
Jan 25 12:29:02: --- last message repeated 1 time ---
Jan 25 12:29:02 Macintosh-6 kernel[0]: disk0s2: I/O error.
Jan 25 12:29:02 Macintosh-6 kernel[0]:
Jan 25 12:29:02: --- last message repeated 1 time ---
Jan 25 12:29:02 Macintosh-6 quicklookd[222]: [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest /Users/Old Ike/Desktop/They Said.WMA>'
Jan 25 12:29:04 Macintosh-6 SyncServer[219]: * -[NSMachPort handlePortMessage:]: dropping incoming DO message because the connection or ports are invalid
Jan 25 12:29:05 Macintosh-6 quicklookd[224]: EXCEPTION CPMessageException: (null)