It sounds to me like you have an option checked along the lines of "extend desktop onto TV".
When I connected my previous laptop to my TV I could have the TV as an extension of my desktop. Try this:-
- Connect your laptop to your TV in the way you have done.
- Open an application (e.g., Internet Explorer)
- Click on the "Restore" button (at the top right of the screen next to close) so the application isn't maximised.
- Click and hold on the title bar of the application and drag it along to the right (or left/top/bottom) of the screen and see if it appears on your TV.
If this is the case then your laptop is working fine and you just need to find a setting to make the TV the same as your laptop screen.
hope this helps