Ok Zone Alarm will cause problems with Ipv6 functionality "toredo tunnel" and running two anti virus's is just asking for problems. When you say you killed them both does that mean disabled or uninstalled? In Zone Alarm's case disabling won't be enough, you will need to uninstall it completely.
As for your Linksys WRT54G, some settings may need to be changed for it to work correctly with Windows 7. That particular router seems to have problems in certain network set ups so you may need to enable the Mac clone function for it to work properly with Windows 7. Try using the procedure below to set your router up correctly for Windows 7.
1) Turn off the modem (Unplug it)
2) Then take the router (Linksys WRT54G) reset it and hold the reset button for 30 seconds.
3) Then open the control page (Internet browser, type in 192.168.1.1, the login and password are set as a default Login: admin Password: admin)
4) Once inside click the MAC Address Clone tab under Setup, enable it then save settings, then switch back to the Basic Setup under Setup. Make sure you are set for Automatic Configuration - DHCP, then change the Local IP Address from 192.168.1.1 to 192.168.2.1 save your settings then close the page.
5) Now turn off the router (unplug it) and turn off the pc (shutdown then unplug it).
6) Your modem should still be off if you forgot to turn it off unplug it and wait 60 seconds, then plug the modem back in, wait till it is completely on and ready to go.
7) Then turn on the router (plug it back in) wait 10 seconds.
8) Then reboot the computer (plug in the power supply and press power on).
After you get your router back up and you are online again, perform an ip/config at the command prompt and check to see if toredo is there.