One laptop blocking internet access of others

Hi, I have 2 laptops that I connect to internet through broadband connection. I have a wireless modem. I use either wire or wireless to connect to broadband. Recently when I got a third laptop, I am facing a strange issue. This new laptop is having problem in connecting to internet. Skype and Gtalk work flawlessly on it, but browsing can be done only through one internet explorer window (do not have any other browser on it). And biggest problem is that, the moment this laptop connects to broadband, other 2 laptops, too, get into the same problem. On these two laptops, internet browsing through IE or Mozilla stops working. Skype and GTalk keep functioning normally though. All laptops have Windows XP on them. Can somebody help?