I use nod32 , with it I don't have problems with viruses ...!

i use NOD32

Best one out there is probably Norton. I mean, look at it.
There are other ones out there that are almost as good for cheap or free, though.
Avira Antivir, I'd say, is best. I went through tons of free ones, including AVG, and Avira just takes the cake. It's got a great shield, not a RAM hog like the others, it's really good. Check it out.

Its McAfee enterprise edition.

Its very fast quick n' clean and fast.

i use nod32 too ... its best !!!