Did you connect other monitor to the PC at the same time? That wallpaper-only window is actually for the extended display when you have a separate main display. You can right-click on the window, click resolution, and choose the TV as "1".
Or maybe the resolution setting is not matching. Make sure the resolution setting is to be native of the TV. If your TV is full HD, then it should be 1920 x 1080.
As poster above mentioned what you're seeing is what usually happen when your current desktop gets extended to the second monitor (TV in this case).
On a laptop you have 2 choices, as mentioned by MKBL you can change the settings in the windows settings, otherwise most laptops have a keyboard function key that can be used to switch between output modes (Laptop screen only, TV only, Laptop Screen + TV...) check your manual.