Not able to connect to my system

Hello,
I took a Airtel broadband connection yesterday. The router settings and the network connections(IP address) have been set. The LAN icon shows that its connected but when I try to open a website it says "Page cannot be displayed" this happens in IE and Firefox. The service people could not figure out what is wrong. I'm using Laptop Compaq nx6320. The router and the phone connections are working fine. could there be a problem in the hardware? I have no idea what to do. Can someone please help me.