Ladies and Gents,
Please click the following link for FREE AVG anti virus. It is good for XP, Vista and 7. I've been running this for well over a year and it has picked up EVERYTHING that is a threat. I opted to have my computer scanned everyday automatically at 12:00 noon "just in case". I also run the free "Tune Up" program also available at the AVG site.
Remember to download the FREE BASIC EDITION, and NOT the trial, unless, of course you want the full blown version.
http://free.avg.com/us-en/homepage