Norton is the worst anti virus out there!! When I had it I had more viruses get on my computer than I care to think.
Fortunately I do not have to worry about getting anything like that because I am a little more computer savvy and I know how the viruses and spyware work.
COMODO Firewall and a real time spyware shield will help with the virus issues along with Avast antivirus and Spyware Blaster. Also never use IE it is nothing but a sure fire way fro crap to get into your computer, use Firefox instead.
My system is set up like Fort Knox and I have never had any issues at all.
Billy