Don't confuse quality with resolution.
A DVD is standard DV, as opposed to the hi-def video you're apparently starting with. Hi-def has about four times the resolution of standard DV.
So, depending on where you're judging the quality (especially if you're viewing it on a computer!) it's not going to look as detailed. But it should look almost as good as the original on a TV.
Please tell us about your Project Preset and your source material - more detail is better.
How are you getting to the DVD process?
How are you viewing the resulting DVD-Video? What types of equipment are you displaying on?
I have burnt HD to DVD before without any quality loss, I have played the edited footage in the adobe viewing window before exporting and it is crystal clear, but when burnt to a dvd it has a compressed look to it when played back on a DVD player. I captured the footage from my HD camera and the settings for export was on the normal setting of PAL Widescreen Dolby, this has worked in the past. When I look at the disc burn image on the disc it looks like a thin band compared to other discs I have burnt which is nearly the full width of the DVD, 44 minutes on the burnt disc looks more like I have burnt a few pictures to the disc. I have unchecked the fit to DVD box and set the slide bar to high quality, but it seems it is still compressing to fit.
This is the first issue I have had with burning, this is an upgrade from 7.0 and the first time I have burnt with it, I even saved the burnt image through adobe to the 4.7 folder and used a third party burning software but still got the same results.
>burnt HD to DVD
Not possible... HD requires BluRay, DVD is, by specification, SD video
You may not know it, but down-resolution from HD to SD is happening during the build and burn
You might want to read over the tutorials, linked in this ARTICLE. You will get some ideas for converting HD to SD.
You will get better results if you downsample from HD to SD in your camera, when you Capture, and then use an SD Project Preset to create your DVD.