If you're willing to pay, grab a copy of Kaspersky. I got an OEM copy (1 year lisence, 1 pc) for about £12. Very easy to use, doesn't hog resources and has an excellent detection rate. Although if you aren't willing to pay, Microsoft Security Essentials is also a very good anti virus. It's the one I recommend to anyone who wants a free AV.

I've been using a combination of Avast! and Ad-Aware. To an extent, it's really just personal preference. I would stay away from AVG, you're right about that. You're going to want an anti-spyware/malware as well as an antivirus.