Ntl do phone, TV and broadband. there is no reason at all why you cannot have just one, any two or all three of these services.
If your BB is currently via a STB you might be moved onto a modem, although many find the TV part only of the modem is deactivated.
The phone line rental is often bundled "free" with some other ntl services like TV, (I say free, there will be a cost buried somewhere and if it goes standalone there will be a rental costs).
Current details of ntls services and pricing :
http://www.home.ntl.com/icat/home