Hello, I'm 99% sure the setting will be on your DVD player. There should be 2 ways to set up the DVD player, basic or advanced. You should be able to fix your problem in either set up, but I always prefer going through the advanced set up.
There will be a setting for your screen type, 4:3, Pan & Scan or 16:9

Make sure that the 16:9 is selected.

Good luck.

High Gloss Cherry
M60 VP150 QS8
Open for Auditions but please don't drool on the High Gloss