If you are "discerning" about your web surfing habits, then I've found Microsoft's Security Essentials to be a decent enough antivirus, and it's free. I put Nod32 on machines where the users are a bit more clueless.
I've had great success with Malwarebytes for dealing with malware-specific problems, as opposed to virus.
I bet it won't be long, if we're not there already, before you really can't make a differentiation between malware and virus.