Did you sort this? If you have a broadband internet connection, it's best to use a router rather than a modem. You can pick them up cheap nowadays. You make one connection into the telephone line just like your modem does. Then you need to connect one patch (Ethernet) cable from router to xbox (for xbox live) and one from router into your PC for your Internet. It's that easy. You can connect to xbox live without turning on the pc - just turn on the router.