Is the rest of your network on a 192.168.80.X? do you have eth0 set to use dhcp to configure its network settings or did you set them manually?
It is set up to use DHCP to configure the network.
It's a typical single NIC setup problem I reckon. Either use two NICs as it was intended or configure the external NIC manually.
Being that I am somewhat inexperienced with setting up network protocol are there any common steps I could use to get my Internet back and just forget the thin client for now?