So...my iBook (G4) freaked and froze a little while ago. I tried force quitting, I tried a few things, and eventually tried putting it to sleep. That worked, but when I woke it back up, a bezel came up saying that I needed to restart the computer. So I just pressed the power button and shut down. Upon starting back up, 30 seconds later, the booting process stopped at a blue-ish screen with a OS Classic style folder in the middle with an icon alternating between the Finder and question mark. Can someone explain to me what is going on and what I need to do now?