As for AV, assuming you mean on windows. I'd suggest BitDefender a lot of people I know use it and seem to like it. Plus they seem to have really good pricing, I recently saw a deal 3 systems for 2 years $31.99
Though things like this:
Seem to indicate that NOD32 and Kaspersky are the best choices. Personally I don't run AV on my home system. I rarely download things (ie: 2 or 3 times a year) and when I do I simply use an online scanner.
I may try NOD32 on a new system I'll be building in the New Year, I just wish it was a little cheaper. 2yrs $60 seems like a lot for a single system.