Remove Run and Temp Items

Performance Mod is a handy homegrown menu driven "app" to use on Windows XP workstations that are misbehaving. It clears temporary items and removes the references to applications that run at startup via the registry. Doing this prior to scanning for spyware and viruses increases the odds of detection and removal while speeding up the scans. This is accomplished by clearing all temp data and exporting and then removing your registry run items. After a reboot your PC should be a little peppier and if you were virus infected there is a good chance that some of them are no longer running as the references have been removed from the registry run locations. After completing anti-virus and anti-spyware scans you can opt to re-add your registry run item by running the batch named "addruns.bat" located in the "regruns" folder on your Desktop.
to Performance Mod.

Performance mod can also remedy a number of known Windows OS issues by applying fixes like: repairing IP stack, removing Pending File Rename Operations and reseting Windows Management Instrumentation and Cryptography service Databases. To aid in post reboot troubleshooting, Application and System Logs are flushed upon completion. We do this because many enties are old and you can trust that any true, recent exceptions will now stand out.

Run an Anti-Virus application

like Sophos Anti-Virus for Windows (must be a Williams student, faculty or staff)
OR
Grisoft AVG AntiVirus

Scan for and remove spyware

Grisoft makes a product named AVG AntiSpyware (formerly Ewido).