Since you have a widescreen TV, just check the DVD for a few key catch phrases that you need for a good widescreen image:
16:9 enhanced for widescreen TVs
Anamorphic widescreen
If it don't say it, you don't get it, and you will be miserable for having purchased a useless DVD. Trust me, I have a ton of them that I purchased before I had the widescreen TV. Thankfully, the movie studios are re-releasing their old DVDs in an anamorphic format. 1.85:1 or 2.35:1, they can both be anamorphic video, its just that the 1.85:1 will fill the screen completely while the 2.35:1 will leave some little black bars above and below. You'll hardly notice. Good luck.