PC runs slow and video is choppy and dlow?

sounds like you have some sort of crazy virus... did you try spybot search and destroy? adaware SE? avast anti virus? after all those i would just back up my data and reinstall windows if nothing works... probably take about an hour or two to install and update from the xp disk. (do a custom install, not repair so it erases everything off your hard drive that you didnt back up to dvd's or an external hard drive or something)