You can't. DVD only allows 720 x 480 NTSC or 720 x 576 PAL. Use BR instead.
From Premiere, use File > Export > Media to open Adobe Media Encoder. In AME, choose "MPEG-2 for DVD" as the Format, and for Preset, choose "NTSC Widescreen Progressive High Quality" (or PAL, as needed). Check the box for "Maximum Render Quality" at bottom of window, this improves downscale quality. Under VIDEO tab, set the data rate accordingly for the length of the program. In Encore DVD project, use "Import > File > As Timeline" and grab both the .m2v and .wav files that you created. Author DVD.
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If you want to keep the fluid motion from the original footage in the footage on the DVD, set the Field Order to either Upper or Lower. Exporting 720p60 to 30 progressive frames looks really bad since half of the frames are thrown away.