Here is a list of the best security freeware to scan your computers.
AVG Anti-Virus Free Edition 8.0.173 (Virus protection)
Ad-Aware 2008 22.214.171.124 (Spyware protection)
Spybot - Search & Destroy 1.6 (Spyware protection)
CCleaner 2.12.660 (Privacy)
Trend Micro HijackThis 2.0.2 (very advanced users spyware remover) There is help available from their user supported community and they are very helpful pointing out problems. Just cut and paste your scan results to the forum
ZoneAlarm Firewall (Windows 2000/XP) 7.0.483 (free firewall)
Most of these are pretty straight forward on how to use. Just make sure you take your time and read the instructions when running any of these. They can all be found at Security Software - Free Software Downloads and Software Reviews - Download.com
If anyone needs any help with these just let me know.