For Norton (yeah i really hate it to): you should always use the norton uninstall and not add/remove programs, the norton firewall is notorious for breaking things (like all internet access) and its a resource hog.
If you don't want to pay for a new subscription, you can just uninsstall/reinstall and it should give you another year.
as for virus protection, i prefer bitdefender (its the most thorough anti virus scanner, but its scan speed are also the slowest because of that).
www.bitdefender.com (they have a free version).
AVG is free and always free forever, but the hueristics (finding suspicious files and new viruses before patches are actually available) and response time (time from the company finding a new virus to releasing a patch) are better.
the most important thing is just to have something that works and you don't totally hate.