What do you mean by "black background with the options buttons"? Are you talking about the black bar at the bottom of the screen? If so, that's because you're capturing images in 4:3. You can go to the settings section of the camera to change the resolution.
thats it, the black bar at the bottom screen, i have had looked into the settings of the camera, and you're right its because of the aspect ratio, and there are two choices, 4:3 or 16:9, but the highest pixel is different for each other,
Regarding camera / photo resolution
(4:3) 16 MP is BETTER than (16:9) 12 MP.
Trust me. The "black bar at the bottom of the screen" is a good thing.