[saltman]

aspect ratio - should be what you shot it in 4:3(full screen) or 16:9(widescreen)

bitrate - depends on the length of the recording. a dvd can use 9800 max which is about 1 hour of video and sound (DVD5) and 2 hours(dvd9). if your footage is longer it will either need to be split into more dvds or compressed. I would say anything below a bitrate of 7000 is not good. but that is personal preference.

make sure you render the video and audio seperately and render in vegas and not in DVDarchitect. use a loop region to render with. select render loop region checkbox. check save markers if you want them... I usually do my tracks in DVDarchitect so I don't use them from Vegas.

for a dvd9
video: file>render as>mpg-2>DVD architect NTSC video stream (full screen template or use Widescreen if filmed in 16:9)
project tab - video rendering qaulity>best
video tab - Variable Bit Rate - click 2 pass - max 9800 avg 9700 min 9600

audio:file>render as>microsoft wav (if you need to resample you can do it here or in DVDarchitect.