Thankyou for your reply. Yes, the final output will be a DVD, but not at 24P. What I plan to do, before creating the DVD, is creating an AVI file and saving that to the hard drive. The AVI will later be burned to DVD.
I assume that Standard Definition AVIs would generally be interlaced. So after editing the interlaced and progressive segments together on the same timeline, when it comes to making the AVI, would Vegas automatically convert the progressive segments to interlaced and at the same time leave the native interlaced segments just as they are?
Or would it be advisable to convert the progressive segments to interlaced before importing them into Sony Vegas?