Windspirit,
The quality will be fine, but it depends on a number of issues. You have to be prepared to compromise, especially if you are burning single-sided 4.7Gb DVDs.
I use variable bit-rate encoding which optimises the filesize. DVD can handle a maximum video bit-rate of 9.8Megabits per sec, with what's left before it maxes out at 10Mbps being available for audio bits.
A lot of older DVD players baulk at much over 8.5Mbps. After I have cut a production, I have to render it from the uncompressed video files to MPEG2 compressed files, in which the video and audio are multiplexed (muxed) together in one bitstream. (The authoring software then chops up the MPEG2 file into the IFO, BUP and VOB files needed to make a playable video DVD).
Now the compromise begins. To get best image quality when there is a lot of movement in each frame requires a high bit-rate. So I try to average 8.5Mbps but allow the rendering engine to go as high as 9.5Mbps. The minimum video bit-rate I use is 192Kbps - used when the picture is stationary or a freeze-frame etc. No point using bits in the MPEG that aren't necessary.
I work with PAL video, which is 25 frames per second, and use resolutions of 576 vertical pixels by 720 horizontal pixels (standard 4:3 aspect ratio television). A 45-minute PAL production can be rendered using 9.5 max, 8.5 average and 192Kbps min and not overflow a 4.7Gb single-sided DVD.
A 1 hour 10 minute production has to be rendered at lower bit-rates to avoid overflow...actually, Nero will burn 4.9Gb to a single-sided DVD so you can fudge slighty and "overburn" without problems.
The important thing to realise is that the longer the production runtime, the lower the average, and maximum video bit-rates you have to use when rendering.
Render at too low a bit-rate and the video will look "blocky". However, if the original source material was shot with a good camera (and especially a good lens), it is surprising how low you can go with bit-rates and still have a very high-quality image when viewed on a non-broadcast quality monitor (i. e. the types of TV most folks have at home.).
Incidentally, for satellite transmission work, we usually go to 13.5Mbps video, maximise at 15Mbps, the rest being available for up to 8 channels of audio. It looks great, but the bit-rate is way too high to use on video DVD.
FWIW, the standard 9Mhz satellite carrier uses a video bit-rate of approx 8.3Mbps, and that's about what most good DVDs average. On that basis, provided the camera lens was good, your DVD video will look very acceptable, far better than VHS or S-VHS.