By the way
to the site.
When you sign up for an NTL broadband connection they will give you a modem that is registered to your address and for you to use. No other modems will work.
So all you need now is a router. As Gareth has said, Linksys do good routers. Just make sure it says its a cable router and not one with built in ADSL modem as those wouldnt work.