3 hours of video (timeline) will not hold on a regular dvd.
Might want to use a double layer.
Or use some thing like DVD shrink or DVD rebuilder to get it to fit.
Dont use match sequence settings might end up with the wrong codec.
Use a preset or set every manually. Export directly to mpeg2-dvd or use DL.
What is the source footage.
———————————————–
Adobe Certified Expert Premiere Pro
Adobe Community Professional