If your TV is not fully displaying your Fire TV screen or your just not sure if it is, here is how to adjust the display for your Fire TV.
1: From the home screen scroll down to Settings.
2: Select the Display & Sounds in the Settings menu
3: Click Display in the Settings menu
4: Select Calibrate Display in the Display menu
5: Use the up and down on your remote to line up the arrows on with the edge of your screen.
*You can undo any changes by selecting reset.
6: Select Accept to apply these changes
Now you can return the home screen and see how it looks.