Wireless Router signal Excellent, but wont connect to Internet!

[mmk64]

I have a Linkysys Wireless Router connected through an Ethernet Card to my Desktop PC (PC1) on which Internet works properly. I have another Desktop PC at home (PC2) with wireless card. I get the signals on PC2 (with messages like "Signal: Excellent" or "Good", but I am unable to access Internet on PC2. Neither IE nor Yahoo Msngr or any other internet interface works.

Please help.
Thanks
Mahesh

 

[Nodsu]

In the router setup, enable internet access for wireless devices perhaps?