Hey guys,
I need help with my computer, I wasn't sure if i should post this in the Help forum or Tech Talk, but I finally decided to post in Help.
Lately my computer has been locking up pretty often. Last night it locked up three times within an hour. First firefox stops responding, and then so does Windows explorer, i cant open the start menu to restart or turn my computer off so I have to do it manually with the power button, I dont really have a problem with doing that, just the locking up is extremely irritating. Does anybody know why this is happening?

Btw, im running windows vista home premium

also, i scanned my computer with AVG and cleared out some tracking cookies that it found, and still it locked up.