Vamsi would like to see the GMail compose window open up inside Firefox (not Internet Explorer) when he clicks any email hyperlink on web pages.
Download the free Google Talk chat application and open the options dialog. You'll see a general setting that says "Open GMail When I click on Email Links" - select that and exit.
This will set Gmail as your default mailto: handler. This means that when you click on any hyperlinked email address, a Gmail compose window will open in your default web browser. The To: address field will be prepopulated with email address.
This trick works if you are in IE - the GMail compose window would open inside Firefox. To make this work inside Firfox, implement this small change:
1. Type about:config in the address bar.
2. Type mailto: and hit enter.
3. You'll see a setting called network.protocol-handler.external.mailto that is set to false. Double click it to toggle the value to true.
Related reading: Replace Outlook with GMail, GMail This! Bookmarklet