All DVDs use only MPEG2. Since you program is only 30 minutes, then render your MPEG file out of Vegas using the DVD Architect template, but hit the "Custom" button and change it to CBR at 8,000,000 and run the quality slider all the way up to 31. This will generate the video portion of the file, you will have to render the .AC3 audio separately. Give it the same name as the video file and DVDA will load them together.
What resolution to create a DVD? I've been using 1920 x 1080 for Bluray - but want to see how much I can fit on a DVD (assuming a lower res for DVD and it will be a smaller file)
Couple of things ... DVDs are fixed resolution, 720x480 for NTSC and 720x576 for PAL. Use any other resolution and it's not a DVD.
File size of MPEG is not based on resolution, it's based on bitrate. Your file won't be smaller just because you render with lower resolution. However, with a lower resolution image you can get away with a lower bitrate and still maintain the same level of quality.
At typical DVD bitrates most folks are happily getting 80 to 120 minutes on a single layer DVD.
Regarding the time limit on a DVD, the amount of editing makes a difference, too. For example, I once heavily edited a movie, including multiple layers and lots of music, and I overfilled a DVD with only 61 minutes of linear footage. Figure with just footage and nothing on top of it, you should get 120 minutes. Your mileage may vary, of course.
As Terry pointed out, the ONLY thing that determines how much "linear footage" you can fit on a DVD is the bitrate at which the audio and video are encoded. The bitrate of the encoding is completely adjustable by the end-user (you.) How complex your video is has absolutely nothing to do with how big it is.
You might want to download this DVD bitrate calculator and use it to determine what bitrate to use for a given length of video.
John, I respect and believe you about the bitrate thing, so now I am even more confused.
I made my first 90 minute movie with no edits and it fit onto the DVD just fine. I went to make a second 90 minute movie with weeks' worth of editing, and it was waaaay too big to fit on the DVD.
The footage was different, but both sets of footage came from the same camcorder. I also set up both projects exactly the same way with the same properies. The only difference was the time I put into editing, and the project with the substantial editing was way too big.
So, I don't know what would have been different to cause such a dramatic difference in file size. I the only setting I changed for both projects outside of using the wizards was to make the render quality "best" instead of the default good. I never changed bit rates, resolution, etc.
I must have clicked on a setting in haste and not realized it, perhaps? Anyway, I have another 90 minute movie which I am currently working on, and I am hoping it will fit on the disc this time...