Vista - No Internet Connectivity Through Router

I have a total of 3 pcs (2 desktops and 1 laptop). The desktops are hard wired to my Linksys WRT54G V.2 and the laptop is connected via wireless. All of the machines are running Windows Vista. I cannot for the life of me get it to let any of my pc's on the internet. Here's what I've done so far.

1. Updated to the latest firmware for the router.
2. Reset to defaults in the router
3. Manually configured IP's and tried DHCP
4. Disabled, uninstalled, reinstalled virus protection.
5. Disabled windows firewall
6. Reinstalled LAN adapter
7. Pinged sites from behind the router (timed out)
8. Pinged sites from the router (works fine)

So this has pretty well narrowed it down to it being the router and the computer not jiving somewhere. I'm out of ideas and pretty green with the ins and outs of vista. All three computers have virus protection and just the windows firewall.