Hi and welcome to the forum! No software firewall is a replacement for a hardware firewall in your router- If that's set up properly, I wouldn't bother paying for a third person software firewall.
I disagree. Most basic home router firewalls are minimalist at best. To get truly efficient firewalling takes either a few bucks or a bit of time in setup. Mind you I'de never allow Norton near a machine of mine and while Vista's firewall is arguably better than XP's that's not saying a lot.
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Obsolescence is just a lack of imagination.