Are you talking about a laptop or a desktop pc???
Well if its a pc you could try opening up the mouse and cleaning it? Use a small cotton bud and take off all the dust and dirt off the rollers, and make sure the surface of the mouse mat is not damaged in any way.
Also make sure there is not any prank software that is running that may be causing this? You can check by pressing ctrl+alt+delete and going to task manager/processes and look for any programs that you dont recognise and end task them.
If all that doesnt work, buy a new mouse.
If its a laptop, thats a different story, try and get an airspray (compressed air) from pc world or something, will cost about £5 and all you do is spray your keyboard, i suggest doing this with the laptop upside down, and something underneath like a piece of paper to styop all the dust ruining your carpet.
If that doesnt work you'll have to get it fixed permamently, and thats another question in itself.
Nadeem, August 2003