Originally Posted by Adraco

Common sense is your best anti-virus protection! If it looks suspicious, don't open it.

If you're an expert and performance geek, then go with Kaspersky, usually quite expensive but you can control everything. If you don't want to worry about stuff, just buy Nortons complete 360 solution with firewall/anti-virus and everything included. It does steal some system resources, but is very user friendly and you never have to worry about things.