Currently Being ModeratedDec 8, 2012 11:28 AM (in response to RaiderJim)
Try this: launch iPhoto with the Option key held down and create a new, test library. Import some photos and check to see if the same problem persists. If it does log into another user account and try iPhoto there. If that also fails then it's a problem with the application and it should be reninstalled. To do so you'll have to delete the current application and all files with "iPhoto" in the file name with either a .PKG or .BOM extension that reside in the:
HD/Library/Receipts folder (10.5 and earlier)
or from the /var/db/receipts/ folder (10.6) .
or from the /private/var/db/receipts folder (10.7 or later)
Then install iPhoto from the source it came from originally.
Currently Being ModeratedDec 8, 2012 7:46 PM (in response to Old Toad)
I tried a new test library, a new user account, and a complete reinstallation of iPhoto 9.4.2. All of these steps failed to resolve the import hanging problem.
I thought that changing my e-mail account from me.com to icloud.com might have messed up something so I changed the account back to me.com, but this did not resolve the problem.
Currently Being ModeratedDec 9, 2012 8:23 AM (in response to RaiderJim)
Book into Mac OS X: Starting up in Safe Mode and see if iPhoto works there. It if does then there's a system component that causing the problem, possibly damaged. A long shot but any port in a storm.
Currently Being ModeratedDec 9, 2012 11:38 AM (in response to Old Toad)
Yes, iPhoto import worked in Safe Mode.
I also noticed in the finder (safe and regular mode) that a right-click on a file and selecting Copy "filename" is not working anymore.
There must be something wrong with my system. Maybe I should try to reinstall Mountain Lion from the App Store.
Currently Being ModeratedDec 10, 2012 9:12 AM (in response to RaiderJim)
It's beginning to look like a reinstall of the system is in order. This Apple document describes reinstalling Mt. Lion: OS X: About OS X Recovery. Be sure you have a backup of your drive so that you don't lose any documents.
This MacWorld webpage also describes the process: Hands on with Mountain Lion's OS X Recovery and Internet Recovery | Macworld