Not a bad idea, I agree a 'hacker" prolly wouldnt give much thought into manipulating youre mouse, although it can be quite easy with a backdoor and some RAS programs (liek vnc or PCA)
Chances are the virus was cuasing the issue, i have seen many cases where wierd anomalies were reported that could only be explained by an infection.
just fyi, if you want a second opine on if you are infected, check out this free Online scanner from Trend Micro (Makers of PCcillin) I recommend this to all of our customers usually:
http://housecall.trendmicro.com