Wrt 120 n router linksys

Hello,
i have wrt120 n router it is connected with my laptop , signal strentgh is strong but when i try to access internet i doesnt work , i am using windows vista and when i go to network and sharing center it shows me a digram of my computer connected to my router but no internet , but my internet is fine , cos i hav a desktop too n internet is working fine plz help , thx