As Ann says, the ONLY format to export to is “MPEG-2 DVD”. Note that DVD is standard-definition, so it is never going to look as nice as the HD original footage, since HD has 5x as many pixels in the image!
Select the “NTSC 23.976p Wide” preset, and the only thing you may need to adjust then is bit rate, dependent on the length of your video.
To determine bit rate, use a calculator such as https://dvd-hq.info/bitrate_calculator.php
Or ballpark it using 560/minutes = rate
For shorter video, do not exceed 8.0 setting.
VBR-2 encoding will yield best results. Also, check the box at the bottom for “Max Render Quality” and that will help with the downscale quality.
The export creates two files, .m2v video and .wav audio. In Encore, use Import As > Timeline and select both of the files at once. Encore will transcode the audio to Dolby AC-3 automatically when you build the DVD.
Good luck
Jeff Pulera
Safe Harbor Computers