I'm using Microsoft Security Essentials now, but historically I haven't even used an anti-virus program. I've only gotten viruses a couple of times over the years, and I was thankfully able to get rid of the viruses by temporarily installing an anti-virus program then uninstalling it immediately afterward. Well, one of the viruses required finding the right program that could deal with the specific virus, but that was the only hiccup. I guess that's the problem with trying to choose one anti-virus program. If you encounter a virus it can't deal with yet, you need to install another program, anyway.
