It's unlikely the mouse is the cause, it seems. But it wouldn't harm to boot without a mouse and see what happens (you can shutdown with alt-f4). Or try another mouse.
I would boot in Safe Mode, run msconfig and go to the Startup tab. Most likely some virus installed itself there. Note the settings (to be able to go back to them later), then uncheck everything you don't know or trust. Work backwards that way until you found a program that does this trick. Let us know what it is.
Hope this helps.
Kees
My mouse is possessed. It starts to move on its own after I am on the computer for just a few moments. It always goes to the start menu and starts to open programs. This happens whether I am on or off the internet. I have ZoneAlarm Pro running and McAfee. I also just downloaded PCillin. I need help because when this happens I do not have control of my mouse at all.

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