Hi Judy,
download the free ZoneAlarm firewall
http://tinyurl.com/ly42 I've used it all my Web life never had a moments trouble with it or a virus. Personally I'd dump Norton Firewall, but if you want, for now just install ZoneAlarm , disable Norton firewall. if you can then get all the pages you want OK uninstall Norton Firewall
But never never connect to the web without a firewall being instaled first.
Goodluck with whatever you do.....but just do as I tell ya ::)and you will be sorted, if Norton is the problem. If your problem persists with Zonealarm running and Norton not, it aint Norton thats the problem.
Its a process of elimination without you going onto the web without a firewall up and running.
I do use Norton Anti Virus, thats good, and I'm running XP Pro SP2 with the XP firewall disabled.