New Linksys WRT-54GL Newbie Help

Please Help.....

I just purchased a new linksys wrt-54gl. The router works and my computer connects okay, but when I open Mozilla Firefox it says "page cannot be displayed." Same is true for Internet Explorer. When I use another wireless connection everything works fine. I also noticed that this same thing happens whenever I try to connect at Panera Bread Co. to use their free Wifi.

Computer: Sony PCG-K45
Windows XP
Mozilla Firefox
Norton 360

I disabled the firewalls (both norton & firefox) thinking that this may not be hindering communication. **Also, when I run the Linksys startup disc it is not "recognizing an internet connection" even when the computer is already connected to the linksys???

I'm a newbie and need some help.

Any and all suggestions/advice is greatly appreciated.

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