What anti virus can I download that’s totally free and that you don’t have to purchase to get rid of the virus?

http://download.cnet.com/Avast-Free-Antivirus/3000-2239_4-10019223.html

Full method security..AV, Firewall, Sandbox without cost for life

http://www.comodo.com/home/internet-security/free-internet-security.php

AVG antivirus it’s totally free and powerful

There a variety of, and most shall be listed in
http://download.cnet.com/.