I'm on a 24" iMac purchased almost exactly one year ago. Last night, out of nowhere, I got the "You need to restart your computer..." dialogue which I have come to find out is something called a kernel panic. At that point, I restarted the computer and it gave me that message again while I was still on the grey screen with the Apple logo. So, I turned it off and unplugged it for a while and then booted back up. Everything seemed to be fine and I used it for a while and then put it to sleep and went to bed. When I woke the computer up this morning it almost immediately gave me that message again. So, I've been doing a lot of reading this morning and trying to figure out what the problem is. I took out my third party RAM and put the original back in, but that didn't change anything. I've tried all kinds of different keys and combinations to hold as it starts up, but only one has done anything: Single User Mode (Command + S). I don't know what to do with that. I put in the install disc, but I can't get it to do anything and now it's stuck in there and I can't get to eject. So, now the computer is at the point that it will get to the grey screen with the Apple logo, but the little spinning gear thing under that won't ever appear. It will either hang here or just keep restarting itself at that point or before it even gets there. I don't ever even get that kernel panic message anymore. I have no idea what to do. Can anyone help?