Microsoft’s Security Essentials, which you can get directly from Microsoft at http://www.microsoft.com/Security_Essentials/ seems to be a pretty good anti-virus program. But be warned there is a fake program with a very similar name making the rounds. The fake one is called Security Essentials 2010. Avoid that one. If in doubt, don’t download from a link or an email link. Go to the microsoft site and download the original.
