I am using Ubuntu 11.04, in dual boot mode with windows7 on a Dell laptop Inspiron 5010

I downloaded and installed in Ubuntu KDE (full version I think-500 oddMbs) as it was advised that this is the best way.

Whatever I do, I cannot connect to the internet either through Konquerer (it appears to have Konquered, vanquished and sent internet into oblivion) nor through Firefox. The wireless internet connection is shown as established; I can open Evolution but cannot connect to any site.

The connection is available and working in windows and Ubuntu. In fact, I am posting this problem from Ubuntu (normal configuration). The settings (preferences) of Firefox in KDE are same as in Ubuntu. Home page is http://google.co.in but firefox in KDE says that it cannot open page.

Could anyone help me access internet. Is there a firewall or something in KDE?