Of course, exact bitrate is going to have a lot of influence on the quality of your final output, and we can't give you the best bitrates to use unless we know the length of your video. DVD HQ has a bitrate calculator I've been using for years that can help with that. It can be found here:

=http://dvd-hq.info/bitrate_calculator.php

Also, make sure you use progressive scan if your source material is progressive. I see in the images posted above he has "lower field first" set, which should only be the case if you are starting with interlaced material.

Good advice from fr0sty to always use progressive if your source is progressive and the DVD spec allows it.

Also, MPEG audio is also possible in PAL countries.

https://www.vegascreativesoftware.info/us/forum/dvd-players-and-mpeg-audio--9616/#ca35240

I can't vouch for it since I live in NTSC land and I was unable to get it to pass through DVD Architect 5.2 without re-encoding in the US.

I think the above advice looks good, but you will get some small pillar boxing bars that will just about be visible on current screens due to the slight difference in ratios between DVD SD formats and HD. If you would like to avoid this, I would suggest nesting the entire original project file within a new project using an SD progressive template and then cropping in slightly to conceal the bars. I have not done this is Vegas for ages, so I may have got that back to front. There is a post on here somewhere from years ago where I described exactly how to set up the crop, but I am not sure if it survived the move from the old server.

Or use the "stretch video to fill output frame size" option on the render screen.

Or use the "stretch video to fill output frame size" option on the render screen.

I would not recommend using that option as if I recall correctly, it actually changes the ratio. In my opinion it is better to crop it and know where you are than flying blind with a distorted image in the render.

Going from 1080 down to SD and with square pixels becoming unsquare pixels (whether it be PAL or NTSC) the image is going to be rearranged anyway. So it probably makes little difference whether you crop or stretch slightly. Personally I prefer to stretch as then you are using all the pixels of your original image whereas with crop you lose some.

As EricLNZ says, the pixels are all being manipulated to downsize anyway. Using stretch gives you the SD equivalent of 16 x 9 .

Going from 1080 down to SD and with square pixels becoming unsquare pixels (whether it be PAL or NTSC) the image is going to be rearranged anyway. So it probably makes little difference whether you crop or stretch slightly. Personally I prefer to stretch as then you are using all the pixels of your original image whereas with crop you lose some.

As EricLNZ says, the pixels are all being manipulated to downsize anyway. Using stretch gives you the SD equivalent of 16 x 9 .

I can not agree with this approach. The crop maintains the ratio. A circle on the 1080 original will appear noticeably slightly oval in the SD reduction if you apply the stretch. Is it more important to retain all of the pixels, or is it more important to avoid a distortion to the overall image? You are already losing thousands of pixels when you scale the image down to SD, I would have thought it desirable to want to keep those that remain in roughly the right place on the screen. With the stretch in place, if you took an image of a square and rotated it on the screen, the square would appear to change shape during the rotation. This for me is an undesirable artifact.

Crops of some form are applied to a lot of stuff that ends up on TV in SD. It is standard practice. I would set the render settings to 'best' in the projects and codec and let the cropped transform take care of it. I regard that to be the best practice. The crop is very slight, it would come nowhere near what used to be regarded as the 'safe zone' that was guaranteed uncropped by CRT TVs

Robert, you are probably correct but I did put your idea to a test. I created a circle using masking. I rendered one version using stretch and one that didn't (which in theory means it kept the same aspect with black on each side but no cropping). I measured the circle on a 21" monitor. On the non-stretched one it was 6 and 3/4 inches horizontal and vertical. On the stretched one the horizontal was about 1/8" wider. In my mind, for the extra work and rendering time, not a big enough difference to change my workflow. But that is what is nice about Vegas, there are many options.

( I am always reminded that many people will watch a TV with a 4x3 screen stretched to 16 x 9, bothers me but not members of my family)