Update: Gotta love it. Genius, I am. Turns out the laptop was on "Power Saver" mode.
About 2 weeks ago my Vista laptop started slowing down. I don't know what caused it, but it started sometime after I updated to service pack 1, although I have no idea if that has anything to do with it. In any case, it's stayed slow and it's getting very annoying.
I've also been losing disk space. As I've gotten closer to filling up the disk I've made a concerted effort to delete items, but each time I do the space inexplicably disappears again.
My CPU usage is hovering at around 30% even when I'm doing nothing. I'm running FireFox 2.0.15 with -safe-mode, but doesn't seem to be helping very much.
I fear I may do something drastic here if I don't find a fix. If you have any ideas let me know.