avg free is the way to go
I used to like it, but it seems to make machines a little bogged down. Avast! or MSE is what I usually recommend. Avast! has a little more tools and options compared to MSE, but both do a good job.
It's generally not advised to have 2 AV programs running at the same time. They tend to not play nice with one another.
I use MSE on 2 of my machines, and AVG Free on 2 others. Both have kept me safe. I also echo uthaman's advice. Doing everything as Admin is the main reason people have problems. Use a lower-privilege account and that will help tremendously.
Can't believe we're 6 comment in and nobody's said "Buy a Mac".
Actually, I believe you can run MSE with another one, I think it works well with Avast! But, as a general rule, just using one works better.
I would swear by Avast! Free...has worked wonders for me and I am not always surfing "safely" (if you saw some of the sites I visit...you would understand)!
I like avast, I use MSE now, but I think their interchangeable. Both run extremely smooth in the background. MSE is very basic and has an easy interface.
Thanks for the feedback everyone, but I'm planning to renew either Webroot or Trend Micro. Anyone have any input on which one is better? Do I need both?
Why pay money, when you can get a free one that is just as good or even better?
But, if you are dying to spend money, go with Trend Micro.