Avast, Microsoft Security Essentials, Avira AntiVir, all did a great job protecting my various computers from the malware that infected this site. Avast is no magic bullet. It didn't do anything that the others didn't do. Of the three I listed Avast is by far the most bloated. Avira is the lightest by a long shot followed by MSE. If you really want to be protected install and use the excellent program Sandboxie. You won't get any malware with it installed.