ChainsawAsh said:
...I'm not an expert in Vegas (or DVD Architect, for that matter).
Try rendering to MPEG2 from Vegas as 720x480, but don't choose 16:9 anywhere. When you bring it into DVD Architect, set it as 16:9 there.
In Vegas (in the 'Save as type:') you can choose 'MainConcept MPEG-2', and then (in 'Template) choose 'DVD Architect 24p NTSC Widescreen video stream'.
It will set the video size at 720x480, and the Pixel Aspect Ration to 1.212 , etc..
This can be loaded into DVD Architect perfectly.
Then, you can do the sound separately, using 'Dolby Digital AC-3 Studio'.
Then set your project (in DVD Architect) to 16:9.