Video AVI file export produces stuttering DVD

When I export a video file as an AVI and burn it to DVD, it stutters upon playback from the DVD, yet when I export it as Windows Media Video and burn it to DVD there's no stuttering. It stutters on my computer and also a clients computer playing it from the DVD drive. There's no stuttering playing the files directly from the HD, just playing them from the DVD.

The original file I got from my client is an AVI file with video and audio about 765 meg in size on a DVD. I added extra sounds to it and if I export an AVI file it's about 765 meg, yet the Windows Media Video file export is about 5 meg. I'd prefer to have an AVI file on the DVD simply because I'm concerned the Windows Media Video file is losing quality being so small in size I assume from being compressed.

I used the Sonar default settings for the Video file exports. I tried to export as a  Quicktime file and kept getting an error message complaining about a compressor setting.

I used Nero to burn a data DVD, because that appears to be what the original DVD was because when I look at the DVD using Windows Explorer it shows up as 1 AVI file on the DVD. I'm using a Sony blank DVD.

Working with Video is new to me. Any suggestions on what to do or where the problem is?