How to eliminate interlaced lines when authoring a DVD

I am having problems with the jagged interlaced lines appearing on the movement in my final DVD. My original source material in FCP 7 is progressive. I am using the default compression settings in Compressor for a "DVD Best Quality 90 min" and burning that file to a DVD in Toast. Any suggestions on what I can do to eliminate these lines on my final product? Im not sure where in the process I should make a change and wanted to ask for suggestions before I start experimenting and wasting DVDs and time.

Ben Rich
Videographer | Technologist
https://sites.google.com/site/benrichfilm/

Thank You, I'll give this a try. I don't understand though why I would need to de-interlace my video if the project is progressive and the target video for DVD is interlaced?

Ben Rich
Videographer | Technologist
https://sites.google.com/site/benrichfilm/