Firstly, don't be too quick condemning your ISP. I am with NTL on Telephone, Digital TV and Broadband and have been for quite a while.
I started with Norwich Cable, which then changed to Bell Cable Media and then Cable and Wireless and now NTL. I have never had any problems with NTL. I have never had any problems using their 0800 052 2000 freephone number. My recent change was from Broadband via my set top box to a modem (which was supplied free). The changeover was so smooth it wasn't true. I think you will find a few other threads from other members complaining about their ISPs (not all NTL) as well. It's a case of "you can please some of the people all of the time" and "you can please all of the people some of the time" but "you can't please all of the people all of the time".
Wait until you get to your new house and see what is best. NTL may not be available at your new location anyway.