Some routers have firewalls, some don't. Those that don't usually try and pass off NAT as a firewall, but it's not the same thing.
If your router has a firewall, the Norton firewall would be pointless. If it doesn't have a firewall, then it might be worth using the Norton one.
I have been told by several people that I don't need to activate my Norton firwall since I have a router.
Do you agree ??