Neither. But if you have to choose, go with norton
With mcaffee, you might as well not even bother. i have it, and it does very little good. our family computer is loaded with viruses. i havn't used norton yet, but i am more than certain that it is better.
If you can put out a few extra dollars, build a small firewall and put smooth wall on it. you won't have any problems again (unless you don't know how to run smooth wall...then your screwed). My linux machine doesn't ever have problems, nor do the computers networked with it that run windows.