This is a very tough question, and one that will have many different answers.
Personally I use Avast, which is free, and I haven't had a virus in years. But then again, Avast may be a pile of Poo and I've just been lucky.
I have tried Nod32 on a couple of PCs and found it to be very effective, it scans quickly, and the PCs it was on remained unaffected. The thing is, I'm a tight fisted old bugger, so object to paying for something when I can get a very effective product for free.
Avast can be found here - click here It's totally free, but does require registration every 14 months. It updates frequently (a few times some days) and scans pretty quickly.
A lot of the technical MS crew are saying you get what you pay for and I have found it have problem updating and finding trojans which NOD32 has found but then I have had Norton in the past and that missed a whole load of the little blitters so you can never be 100% What do you thnk?
I don't think there's a 'best' of anything it's just finding whhat works either for your pocket or your particular needs or requirements. I've never paid a penny for anti virus software as I've seen the free downloads often out perform the 'pay for' ones.
Pay for NOD32. Free avast! 4, Been using it since it was introduced with only one problem and that was quickly rectified using their free e-mail support. Top product for those that qualify for the free license. For the first year I double checked occasionally using web based scanners like Trend click here and Panda click here They simply confirmed that avast! was doing the job and now I just leave it to do its thing.
I think bogbrain has hit the nail on the screw, you could try before you buy, there are FREE Antivirus progs that are more than capable of protecting a home user PC, but much of it will be down to you and where you point the thing, stay away from sites your not sure of, Email attachments your not sure of. As for finding AVG a bit suspect, not sure what you mean by that, i use it, can't fault it, others on this forum have their favourites, you have to remember that diferent progs will detect diferent things so ere on the side of caution have a regular PC housekeeping and BACKUP system in place and you should be OK,good luck..