1. Disable your XP firewall; go to the control panel, double click on Windows Firewall, check the disable box. Two software firewalls will give you less, not more security. And besides, XP firewall 'does' clash with Norton FW & cause problems.

2. Configure Norton firewall. Have a look at these (a) Configuring Norton Internet Security, & also (b) Reconfiguring Norton Firewall

3. Not sure what you can do about the wireless NAT firewall as almost all wireless devices do have such firewalls. But if configuring your software firewall is good enough, then perhaps this can be ignored as you had before.