Right now I'm using AVG on the main computer.
I have a few computers. On the main secondary, I'm running Avira.
I have another box with Avast!
Then I have two, that are running Linux distros, with no AV software whatsoever. As I understand it, there are very few viruses that are written for Linux.
I did have the Norton virus for a while, but decided that it was not the greatest.
Avast and Avira are really good programs, but the user interface is lacking in ease of use. That's just my personal opinion.
AVG is the most well rounded and easy to use AV program. That is not to say that I've not had a a few problems out of it.
I don't really worry about viruses too much. I always back up all of my important data. I don't mind reinstalling my operating system from time to time.