Hi, I have a Magnavox #CD130MW9. It was working

Your set has a built in DVD player, which has a Zoom Function. Look on the remote for a button that says Aspect Ratio, or 4:3, or 16:9 or something in the dvd button area. If all else fails, try this; Press every button one at a time (the ones you are'nt sure of what they do) until you see a change in the screen size. If this doesn't work, you might unplug it and replug it in (electric that is) if nothing, leave it unplugged overnight to clear all settings. **Beware, if you have had to set-up this tv unplugging it overnight will cause you to have to do all that again, so its a last resort fix**