'Been there, done that'. Verdict: Kaspersky, Anti-Vir, BitDefender, Pc-cillin in that order.

IMO BTW - no flaming! =P

EDIT: Norton never makes the list..ahahahaha - stupid bloatware. I can't tell you how many problems i've had with that sorry excuse for a program. Where'd they get their IT/engineering degrees anyway? Off the back of a cereal box? (i couldn't help myself >D)