I am having a very similar situation with same system and OS. I have seen in this and other forums about running a scan with EtreCheck. In the event that the results of a scan might offer anything helpful, I am posting my results. Maybe you should do the same, Redlee.
Problem description:
Running OSX Yosemite 10.10.1 on a 2009 27" iMac. System is hanging on startup.
It seems that everything I have read so far on similar issues has called for a running of EtreCheck and a submission of the results, so I have chosen to start off with that first thing.
EtreCheck version: 2.1.6 (109)
Report generated January 21, 2015 at 10:43:17 AM EST
Download EtreCheck from http://etresoft.com/etrecheck
Click the [Support] links for help with non-Apple products.
Click the [Details] links for more information about that line.
Click the [Adware] links for help removing adware.
Hardware Information: ℹ️
iMac (27-inch, Late 2009) (Technical Specifications)
iMac - model: iMac11,1
1 2.66 GHz Intel Core i5 CPU: 4-core
8 GB RAM Upgradeable
BANK 0/DIMM0
2 GB DDR3 1067 MHz ok
BANK 1/DIMM0
2 GB DDR3 1067 MHz ok
BANK 0/DIMM1
2 GB DDR3 1067 MHz ok
BANK 1/DIMM1
2 GB DDR3 1067 MHz ok
Bluetooth: Old - Handoff/Airdrop2 not supported
Wireless: en1: 802.11 a/b/g/n
Video Information: ℹ️
ATI Radeon HD 4850 - VRAM: 512 MB
iMac 2560 x 1440
System Software: ℹ️
OS X 10.10.1 (14B25) - Time since boot: 1:9:36
Disk Information: ℹ️
WDC WD1001FALS-40U9B0 disk0 : (1 TB)
EFI (disk0s1) <not mounted> : 210 MB
Macintosh HD (disk0s2) / : 999.35 GB (471.59 GB free)
Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB
OPTIARC DVD RW AD-5680H
USB Information: ℹ️
Apple Internal Memory Card Reader
Apple Inc. BRCM2046 Hub
Apple Inc. Bluetooth USB Host Controller
Generic USB Storage
Apple Inc. Built-in iSight
Apple Computer, Inc. IR Receiver
Configuration files: ℹ️
/etc/sysctl.conf - Exists
Gatekeeper: ℹ️
Mac App Store and identified developers
Kernel Extensions: ℹ️
/Library/Application Support/Roxio
[not loaded] com.roxio.TDIXController (2.0) [Support]
/Library/Extensions
[not loaded] at.obdev.nke.LittleSnitch (4228 - SDK 10.8) [Support]
[not loaded] com.leapfrog.driver.LfConnectDriver (1.11.1 - SDK 10.10) [Support]
/System/Library/Extensions
[not loaded] com.Belcarra.iokit.USBLAN_netpart (3.1.1 - SDK 10.6) [Support]
[not loaded] com.Belcarra.iokit.USBLAN_usbpart (3.1.1 - SDK 10.6) [Support]
[not loaded] com.Cycling74.driver.Soundflower (1.5.2) [Support]
[not loaded] com.IKMultimedia.driver.StompIO1 (1.0.0) [Support]
[not loaded] com.RemoteControl.USBLAN.usbpart (3.1.1 - SDK 10.7) [Support]
[not loaded] com.ShapeServices.driver.HSAudioDevice (1.0.5 - SDK 10.6) [Support]
[not loaded] com.ikmultimedia.driver.StealthPedal (1.0.0) [Support]
[not loaded] com.leapfrog.codeless.kext (2) [Support]
[not loaded] com.mice.driver.Wireless360Controller (1.0.0d12 - SDK 10.8) [Support]
[not loaded] com.mice.driver.WirelessGamingReceiver (1.0.0d12 - SDK 10.8) [Support]
[not loaded] com.mice.driver.Xbox360Controller (1.0.0d12 - SDK 10.8) [Support]
[not loaded] com.orderedbytes.driver.ControllerMateFamily (4.4.3) [Support]
[not loaded] com.roxio.BluRaySupport (1.1.6) [Support]
[not loaded] com.vara.driver.VaraAudio (1.0.2) [Support]
[not loaded] net.telestream.driver.TelestreamAudio (1.1.0 - SDK 10.8) [Support]
[not loaded] org.walisser.driver.DWXBoxHIDDriver (1.3.4) [Support]
/System/Library/Extensions/2.2.0/Belcarra.USBLAN_netpart.kext/Contents/Plug-Ins
[not loaded] com.belcarra.iokit.netpart.panther (1.6.3) [Support]
/System/Library/Extensions/2.2.0/Belcarra.USBLAN_usbpart.kext/Contents/Plug-Ins
[not loaded] com.belcarra.iokit.usbpart.panther (1.6.3) [Support]
/System/Library/Extensions/2.2.0/RemoteControl.USBLAN_usbpart.kext/Contents/Plu g-Ins
[not loaded] com.RemoteControl.USBLAN.panther (1.6.2) [Support]
/System/Library/Extensions/ControllerMate.kext/Contents/PlugIns
[not loaded] com.orderedbytes.driver.CMADBDevices (4.3.10) [Support]
[not loaded] com.orderedbytes.driver.CMUSBDevices (4.4.3) [Support]
[not loaded] com.orderedbytes.driver.CMUSBKeyboard (4.4.3) [Support]
[not loaded] com.orderedbytes.driver.CMUSBPointer (4.4.3) [Support]
Problem System Launch Daemons: ℹ️
[failed] com.apple.ucupdate.plist [Details]
[failed] com.apple.watchdogd.plist [Details]
Launch Agents: ℹ️
[not loaded] at.obdev.LittleSnitchUIAgent.plist [Support]
[not loaded] com.coupons.coupond.plist [Support]
[not loaded] com.micromat.TechToolProAgent.plist [Support]
[not loaded] com.oracle.java.Java-Updater.plist [Support]
[invalid?] com.orderedbytes.ControllerMateHelper.plist [Support]
Launch Daemons: ℹ️
[not loaded] at.obdev.littlesnitchd.plist [Support]
[not loaded] com.adobe.fpsaud.plist [Support]
[not loaded] com.edb.launchd.postgresql-9.0.plist [Support]
[not loaded] com.leapfrog.connect.authdaemon.plist [Support]
[not loaded] com.lsreset.plist [Support]
[not loaded] com.mice.360Daemon.plist [Support]
[not loaded] com.micromat.TechToolProDaemon.plist [Support]
[not loaded] com.oracle.java.Helper-Tool.plist [Support]
[not loaded] com.oracle.java.JavaUpdateHelper.plist [Support]
[invalid?] com.trusteer.rooks.rooksd.plist [Support]
[not loaded] jp.co.canon.MasterInstaller.plist [Support]
User Launch Agents: ℹ️
[not loaded] com.amazon.music.plist [Support]
[not loaded] com.google.keystone.agent.plist [Support]
[not loaded] com.google.xupdater.plist [Support]
[not loaded] com.leapfrog.connect.monitor.plist [Support]
[not loaded] com.pia.pia_manager.plist [Support]
[invalid?] com.plexapp.helper.plist [Support]
[not loaded] com.skype.c2c_service.plist [Support]
[not loaded] uk.co.markallan.clamxav.freshclam.plist [Support]
User Login Items: ℹ️
AppDelete Application Hidden (/Applications/AppDelete.app)
Caffeine Application Hidden (/Applications/Caffeine.app)
Meteorologist UNKNOWN Hidden (missing value)
Dropbox UNKNOWN Hidden (missing value)
SpeechSynthesisServer Application (/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks /SpeechSynthesis.framework/Versions/A/SpeechSynthesisServer.app)
BetterTouchTool UNKNOWN (missing value)
BetterSnapTool Application (/Applications/BetterSnapTool.app)
ClamXav Sentry UNKNOWN (missing value)
VMware Fusion Start Menu UNKNOWN (missing value)
Phone Amego UNKNOWN Hidden (missing value)
ClamXav Sentry UNKNOWN (missing value)
My Living Desktop Viewer UNKNOWN (missing value)
Pogoplug Backup UNKNOWN (missing value)
HP Scheduler Application (/Library/Application Support/Hewlett-Packard/Software Update/HP Scheduler.app)
Internet Plug-ins: ℹ️
Default Browser: Version: 600 - SDK 10.10
Silverlight: Version: 5.1.30317.0 - SDK 10.6 [Support]
FlashPlayer-10.6: Version: 16.0.0.257 - SDK 10.6 [Support]
Flash Player: Version: 16.0.0.257 - SDK 10.6 [Support]
QuickTime Plugin: Version: 7.7.3
iPhotoPhotocast: Version: 7.0 - SDK 10.7
eMusicRemote: Version: Unknown [Support]
CouponPrinter-FireFox_v2: Version: 5.0.3 - SDK 10.6 [Support]
npDDRia: Version: 0.0.14.2 - SDK 10.9 [Support]
EPPEX Plugin: Version: 10.0 [Support]
eMusic: Version: Unknown
JavaAppletPlugin: Version: Java 8 Update 25 Check version
User internet Plug-ins: ℹ️
CitrixOnlineWebDeploymentPlugin: Version: 1.0.105 [Support]
ooVooWeb: Version: 1.0.3 - SDK 10.6 [Support]
Safari Extensions: ℹ️
AdBlock [Installed]
Adblock Plus [Installed]
FatWallet Express [Installed]
clea.nr Videos [Installed]
3rd Party Preference Panes: ℹ️
Flash Player [Support]
FUSE for OS X (OSXFUSE) [Support]
Java [Support]
TechTool Protection [Support]
Time Machine: ℹ️
Time Machine not configured!
Top Processes by CPU: ℹ️
3% WindowServer
0% fontd
0% loginwindow
0% dpd
Top Processes by Memory: ℹ️
455 MB Safari
198 MB com.apple.WebKit.WebContent
137 MB Finder
94 MB WindowServer
77 MB CalendarAgent
Virtual Memory Information: ℹ️
4.03 GB Free RAM
3.36 GB Active RAM
538 MB Inactive RAM
649 MB Wired RAM
948 MB Page-ins
0 B Page-outs
Diagnostics Information: ℹ️
Jan 21, 2015, 09:34:24 AM Self test - passed
Jan 20, 2015, 02:24:18 PM /Users/[redacted]/Library/Logs/DiagnosticReports/fontd_2015-01-20-142418_[redac ted].crash
Jan 20, 2015, 02:24:10 PM /Users/[redacted]/Library/Logs/DiagnosticReports/fontd_2015-01-20-142410_[redac ted].crash
Jan 20, 2015, 02:24:06 PM /Users/[redacted]/Library/Logs/DiagnosticReports/fontd_2015-01-20-142406_[redac ted].crash
