Oh boy, what did 10.6.2 do to my iMac file sharing?

Hi all, I upgraded two machines to 10.6.2, an imac and an mbp, both newer but not the newest. All seemed well but for one problem with the imac: file sharing is really hosed. In the system preferences pane/Sharing I now get this behavior:
1) File Sharing: On, but there are no longer any shared folders or users. I can't add any either.

2) If I click Options, I see that Share files and and folders using AFP is checked, as is Share files and folders using SMB (Windows) with the proper Account ticked on.

3) If I try to share a new folder, then tick off Share files and and folders using AFP, it turns to "-" and file sharing is shut off immediately - and then ALL **** BREAKS LOOSE! I lose keyboard, can't open programs, can't use task bar, and icons clicked on the dock disappear.

Here are the events in a less emotional printout:

Warning 11/13/09 9:09:29 PM LSSharedFileListInsertItemFSRef returned NULL for path:/Volumes/StudioC/8.Downloads
Notice 11/13/09 9:09:29 PM TabletDriver[307]: CarbonCore.framework: coreservicesd process died; attempting to reconnect but future use may result in erroneous behavior.
Notice 11/13/09 9:09:29 PM coreaudiod: CarbonCore.framework: coreservicesd process died; attempting to reconnect but future use may result in erroneous behavior.
Warning 11/13/09 9:09:29 PM (com.apple.coreservicesd[188]) Job appears to have crashed: Segmentation fault
Notice 11/13/09 9:09:29 PM TabletDriver[307]: CarbonCore.framework: coreservicesd process died; attempting to reconnect but future use may result in erroneous behavior.
Notice 11/13/09 9:09:29 PM 2009-11-13 21:09:29.689 ReportCrash[1461:2a03] Saved crash report for coreservicesd[188] version ??? (???) to /Library/Logs/DiagnosticReports/coreservicesd 2009-11-13-210929localhost.crash
Warning 11/13/09 9:09:34 PM ### Error:268435459 File:/SourceCache/SharingPref/SharingPref-193/Shared Classes/SambaUsersSheetManager.m Line:265
Notice 11/13/09 9:09:57 PM _RegisterApplication(), FAILED TO REGISTER PROCESS WITH CPS/CoreGraphics in WindowServer, err=-50
Notice 11/13/09 9:09:58 PM _RegisterApplication(), FAILED TO REGISTER PROCESS WITH CPS/CoreGraphics in WindowServer, err=-50
Warning 11/13/09 9:10:12 PM * WARNING: Method selectRow:byExtendingSelection: in class QSTableView is deprecated. It will be removed in a future release and should no longer be used.
Warning 11/13/09 9:10:29 PM ### Error:268435459 File:/SourceCache/SharingPref/SharingPref-193/Shared Classes/SambaUsersSheetManager.m Line:265
Warning 11/13/09 9:10:31 PM ### Error:268435459 File:/SourceCache/SharingPref/SharingPref-193/Shared Classes/SambaUsersSheetManager.m Line:278

This looks pretty bad and the behavior has to be the worst I've ever seen on a mac...it's like the entire system becomes unstable. I've tried all the usual things like Checking Permissions and running Disk Warrior. I even ran Applejack auto figuring I could not hose this up anymore. But nothing seems to fix it. The MBP however is just fine with filesharing and 10.6.2, so this seems to be imac specific. Both machines are configured with pretty much the same software.

Another worrying error message in console is this one, only because if I ever get the above resolved, this machine goes back to FCP editing:

Error 11/13/09 9:00:44 PM Error loading /Library/Audio/Plug-Ins/HAL/DVCPROHDAudio.plugin/Contents/MacOS/DVCPROHDAudio: dlopen(/Library/Audio/Plug-Ins/HAL/DVCPROHDAudio.plugin/Contents/MacOS/DVCPROHD Audio, 262): no suitable image found. Did find:
/Library/Audio/Plug-Ins/HAL/DVCPROHDAudio.plugin/Contents/MacOS/DVCPROHDAudio: no matching architecture in universal wrapper