convert avi to DVD with black bars!

[insc]

hi

I would like to know how to convert a avi movie I have here to *.m2v (TMPGEnc) (DVD) but with those black bars. to make the video in a better quality, like when I normally convert it gets streched ...
So if possible, could someone help me add those black lines in the movies?
Preferable with TMPGEnc but if someone has the explination using another program, please explain..

ty,
Tiago Cabaco.

[setarip]

In TMPGEnc:

Click the "Advanced" tab and change applicable settings to: "16:9 Display", either "Fullscreen (Keep Aspect Ratio)" or "Center (Keep aspect ratio)"