Why does the center of the video look normal, while the sides look streched?

Ive been trying to solve this myself, but its hard to find an answer when you arent sure what its called.
I just got nero 7 ess, and on all my burned dvds, the center of the tv screen looks normal, while the sides looked warped and streched.
Its like you filmed it through a fish eyed lens.
Heres as much detail as i can think of:

the original video file was 16:9
the tv is 16:9
the dvd player is set to 16:9 (ive tried changing every aspect)
zoom features on the tv and dvd have been adjusted
ive tried both a 4:3 and my computer it has the same problem.
Ive used this burner with ashampoo and do not have the same problem

I know this has to be a setting in nero, but ive gone over it numerous times and cant seem to find anything.
anyone wanna float some help my way?