I have been running Leopard no problems till 2 days ago. Now I cannot shut-down without turning the iMac off, otherwise I get a continuous grey spinning ball when trying to shut-down. (Have waited up to 1/2 hour before turning imac off via holding down off/on button) The problem started when (I think) I did not properly eject a USB flash drive. Some notes: - I can start-up & run programs fine. (does start-up slower though) - tried repair permissions - now the backup external drive (USB) is not 'seen' by Time Machine - Tried unplugging all USB devices (printer, backup drive) & restarting: no luck - startup in safe mode (shift key down). Starts/runs fine but same spinning grey ball when trying to shutdown Thoughts?