My 2010 iMac is having a problem. I was working with some different Linux distros a while back and I had an issue that I resolved with not being able to delete or edit harddrive partitions. Now, I want to install Lion and I am getting an error about how my HD cannot be used for startup, or something like that. I have looked in to the solution for this, but it seems I need to boot from a Snow Leopard disk so I can use Disk Utility from a CD. Here is the problem now. I start up and hold the "c" key to boot from disc. The disk starts to spin and the apple logo comes up but after a minute or two the disk stops spinning and my computer just sits there until I hold down the power button to restart. At first I thought it was my disk (a retail copy of SL) so I acquired an disk image and burnt a new copy. Still has the same problem. It will still boot just fine from any of the Linux CDs I have tried. I have tried resetting the PRAM.