if you are using a set top box, you will have to either register the router with ntl, or clone the mac address of the pc onto the router. Have you done either of these things?
If not, connect the router back in and powercycle everything. Then try browsing to
http://start.ntl and following the process through.
If you can't get to that page, go to the routers config page (which btw is
http://192.168.1.1/ ) and check what ip address the router is getting. Does it start 10, 169, or something else?