Weird iBook problem

I've been at school, and although I've had my iBook here, I rarely use it. On Friday, I went home and downloaded a few updates (iTunes 7.0.something and a security update, I believe). After I installed these two updates, I restarted like it told me to, and things seemed to be fine. After a few minutes, my screen went grey and a black box came up with the power button icon and it told me to restart in like 5 different languages, so I did. Everything came back up fine, but then again after a few minutes, my screen got fuzzy or something (I really don't know how to explain it) and the iBook froze. I restarted it, and after a few minutes it did it again. It has done it everytime I've tried to use it since then, and it's starting to upset me. I don't know if something happened with the update, or if it got bounced around or something on the ride home from college on Friday afternoon. Any help would be greatly appreciated. Thank you.

Sounds like a kernel panic.

See here for more info.

Is there a way to uninstall a specific update, or would I have to reinstall the entire OS, assuming it's a software problem.