|Try connecting direct from modem to one of your PCs|
Do you get internet? If so then run "ipconfig /all" in command prompt to obtain your internet settings.
Note. You do not connect to your network through the WAN port
Your network is the LAN side of the router. It is the modem that connects to the WAN port and you may need to go into your router admin interface and manually configure the WAN settings to match those you obtained from ipconfig.
Some ISPs configure their internet to the specific MAC address of the first PC. You may need to clone that mac address in the router in order to get a WAN connection.
Goin' Fishin' (Some day)