I've got two desktops, two laptops and a MacMini connected through a Linksys router to Telewest Cable. I would suggest that connecting multiple computers with Cable is probably much easier to set up than ADSL.
<<< I've decided to sign up with Talk Talk anyway >>>
Read the "small print" very carefully. I've heard that what they are offering is not nearly as attractive as it first appears once you go into it in detail. I've also heard that, if you do have any problems with the service, getting any sort of advice or help can be extremely difficult.