Sometimes issues with spyware or viri will definately screw up your mouse/touch pad. Suggest an independent online virus scan at
http://housecall.trendmicro.com/ and if you dont have any spyware programs/utilities, suggest downloading, installing then updating SuperAntiSpyware free edition then running it. SpywareBlaster is another good one that runs in the background. Just keep it updated every few days. Keeps spyware from loading