As usual, there is no single answer to your question but here's an example: from Adobe Premiere 6.5 export using the Main Concept MPG encoder. Select a DVD profile and in the multiplexer tab, select DVD. This will export a single mpg file with both video and WAV audio included. Drag this file into Sonic MyDVD and select a background. When you go to burn a disk things go fairly quickly because the file is already converted to MPEG-2.
Now for the exceptions. Some authoring software demands separate audio and video files, which the Main Concept encoder will make by default if you don't select DVD under the multiplexer tab. In these cases you drag both audio and video into your authoring software (DVD Workshop, for example). Some apps will convert WAV to AC-3 (dolby) which is a better (because smaller) format for DVD, leaving extra bits for video quality on a 4.7 GB disk - but the licensing adds several hundred dollars to whatever app contains it.
You are right that much of the authoring software offers to capture, edit and burn, and some only offer chapter points while capturing so if you've already converted you can't add chapters. There is no solution that doesn't require some learning beyond the NLE, unless you just want an appliance that will take digital in and spit out DVDs.
David Hurdon
http://www.contentshop.tv