If you got a really good deal on the PC and don't want to get ride of it you could format the drive and put Win 7 on it. If you have a family member in school, MS has a deal where you can get Win 7 for ~$30.
I personally don't use any norton products any more. If you want you can get a free version of Avast and the free version of Comdo Firewall (install the firewall only). You would dl these two programs, then disconnect from the internet, then uninstal all your old security software, then reboot, then install the new stuff. Only after everything is installed would you connect to the internet.
An even better thing to do is after uninstalling the old software, run http://www.ccleaner.com/ with it registry cleaning option to clear out the old norton stuff, followed by the reboot.