Windows Vista and Cablecom Wireless internet connection

I purchase a new Dell Inspiron 6400 and got the wireless internet connection (Siemens router) from Cablecom. It has been 3 weeks and I still cannot connect to Internet. The computer recognizes the router, but I cannot get into any webpage, not even connecting the cable modem directly to the computer via an ethernet cable. I called Cablecom probably 7 times, and they have told me that the network adapter is not compatible with Windows vista and that I should update the driver. Can somebody help? I have no idea what to do. Windows Vista has so much problems. I cannot even use my Nero Vision program because it is not Vista certified.... I wished I could have been told that and gave the choice to choose my operating system. In my old computer, Windows XP was working wonderfully.