3 Questions Regarding Router...

Personally, I kinda like Norton Personal Firewall, but that's just me.

As for the other stuff, you should be able to detect your router via Win XP, so seeing the netgear router is not an issue, and the Sis network adapter is cool too, so long as you are trying to connect via a LAN cable (remember, that your LAN card is integrated and the mobo is made by Sis... therefore it's supposed to say that it's by Sis).

If you're trying to connect via WiFi though, and you cannot see the Atheros card in your device manager, then you have an issue and probably need to reinstall the drivers and the like. Since you said that you are connecting via wire, this is a moot point.

Personally, I've had great luck with the integrated network adapter.

One off the wall potential problem that you might have connecting to your router would be this. Some of the Linksys and Motorola cable modems have this annoying tendency to freeze up becuase they cannot get an address from the router quickly enough. I noticed this issue while using Bit Torrent, and was originally told that the issue was my router (a MN-500 by MicroSoft). Just to check, I decided to jack the modem directly into my laptop and see what was going on. Sure enough, the same problem occurred. My theory is that the tech from Comcast was correct in identifying the basic cause of the problem, but that it was the modem itself to blame and not the router (that said, I recommend people away from this router... I prefer the higher end Netgear and the newer Linksys routers made with the Cisco chipsets).

Hope this helps.