[MovedGoalPosts]

Broadband supplied by STB uses an ethernet cable which has a USB adaptor plugged in at the computer end. It should be possible to simply unplug that adaptor.

To convert over to using ethernet, power off the STB, swap the cables over from USB to ethernet and plug the ethernet into the network card in your PC. If you don't have an ethernet card, these are available from any decent high street computer shop for around a tenner. When you power up the STB, let that settle, then power up the PC. The first time you then try to browse the internet you will be taken to ntl's registration page. You'll need the details ntl originally sent you for your account password and stuff.

If you connect a router so you can add your laptop, you again need to power off the STB, connect up the wiring, then power on the STB, then router, then PC(s). The router would be seen by ntl as a new computer, so again when you first browse you'd be taken to the ntl registration screen.