Hey guys, question for you and I'm hoping you can help. I'm selling my July 2010 iMac to my parents' neighbor and I want to wipe the system and do a clean re-install of Snow Leopard. I know how to do so (follow the directions on this page) and besides it's pretty easy anyway. The problem is, I lent the disk that came with my computer to a friend over the summer and I only just got it back. I'm pretty sure it's scratched beyond recognition because when I try and boot from the disk and hit Option, only the main hard drive appears. Alternatively, if I hold down C, I can hear the disk spinning but it never reads it and if I let go of C, it just boots to the main drive. Is there a way I can do a full system re-install without the disk? I remember reading somewhere on an Apple support site that I can only do a system re-install like this with a Snow Leopard for iMac disk, is that true? Might it be possible instead to use the Leopard install disk that came with my Dad's iMac?