Die, computer, die die., Help greatly appreciated. Options

[*evdxgirl*]

Okay, so lately, my computer has been totally screwing up. This is what has happened:

One day, after doing nothing different on my computer, it decides to completely spaz on me. Okay, so I usually have my passwords saved/remembered for websites like this, and xanga. However, now my computer requires me to log in EACH AND EVERY TIME. This happens even if I click 'remember my username' or whatever. And, sometimes, I'll just be doing whatever on createblog/xanga, then my computer will redirect me to the login page again. I just got logged off randomly. This sometimes happens like every 10 minutes, and I don't know whats happening. And so I check my history, and everythings gone. And my history resets itself every day, so ... yeah. I hate my computer.

I tell my dad, and he runs a virus check with Norton, but nothing comes up.

What's happened? All you computer geniuses, help please! I'll greatly appreciate any information that's offered.

Oh yeah, this has happened before one time, then it fixed itself. ...