For someone who doesn't know much about computers you seem to have alot of security programs on your system.
1) It could be that one of those programs is conflicting with another
2) You mentioned that you download bit torrent programs; these are notorious for having malware/ viruses, etc. attached to them.
3) Use one of those security programs (preferably Super AntiSpyware) to do a "Deep Scan" of your entire sysem, it's possible you've picked up a virus.
I know next to nothing about computers, so forgive me for sounding like a computer ******.
Using XP, with McAfee SiteAdvisor, Comodo Firewall, Spyware Doctor, Malwarebytes, McAfee and Super Antispyware. I was downloading a torrent and was on a site I regularly go to when this happened.
My mouse pointer suddenly went crazy today. It would jerk to the left every time I tried to move it around, so it made clicking anything impossible. And when I left it alone the arrow would continuously edge to the upper left. I couldn't close windows because the same thing happened when I switched to my laptop's touchpad, so I had to pull the plug and the battery to reboot it.
And one other thing. The Start window (or whatever you call the window that appears when you press the Start button on the desktop) would flash for a while then stop, though that may have been because I tried pressing the Escape button (which didn't work).
I'm on the same laptop now. Everything's working fine so far, but I'm keeping an eye on things. Anybody have an idea on what happened?

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