I've been searching all day trying to figure out this problem. I have 2008 24" iMac 3.06 GHZ Intel Core 2 Duo (snow leopard). This morning I was doing something and the iMac froze and I saw the infamous spinning wheel. After a while I had no choice but to hold down the power button and try a restart. Now all that I get is the spinning wheel of death at the beginning of start-up. I tried restarting holding the "Shift" key (no good). I tried restarting holding Alt, Command, P, R (no good). I'm a complete novice at trying to fix anything on a mac so some of the other suggestions I read about don't make a lot of sense. I have about 85% of the iMac backed up the an airport extreme and was about to do another backup and this happened. I really need the missing files. Any advice for someone who doesn't know a lot about these type of things? Many thanks! ps - I have access to another mac for a while.