I have an iMac mid 2007 2ghz Core 2 Duo, 3gb ram, running Mountain Lion and I've started having a problem. Initially, I would get freeze ups of programs but the mouse pointer would still move around screen. This would seem to mainly happen in the first 5-10 minutes of use and after that all would be okay. I did a verify permissions, it found a couple of things and seems to be worse. Now also out of the blue, I've been in the middle of something and it would just reboot with a message that my computer had recovered from a system crash. I did a disk check and it reported no problems. Anyone got any ideas what is going on? Is it Mountain Lion not playing properly or is something else going on. I'm seriously considering going back to Snow Leopard or even Lion.