to the site
Thats right, you need the router as that allows you to share the connection, and the wireless cards in each PC so they can talk to the router.
The router will then have a WAN or Internet port and that is where you plug the NTL modem in.
You may or may not have a modem at the moment. You must use the modem supplied by NTL. Once you get an account with NTL (if you dont already have one), they will provide you with the broadband modem.