I think you are misunderstanding something important here. A blank DVD is a blank DVD. It can be used to burn either data, in which case it is just a storage bin for that data, and the DVD would then be called a data disc. Or it can have video burned to it in a certain format, contained in a Video_TS folder and using all those different extensions (.vob, .ifo and .bup). Moreover, it will have some lead-in code inserted during the burning process. And this is recognised by a DVD player as making it a video DVD.Will this work on both data disc and DVD disc?
But the crucial thing is that video and audio files are just that: binary files like any other data -- documents, photos, Adobe PDFs etc. And they can be stored on a DVD like any other data. And then later read by a computer and any editing software for later conversion into a Video_TS folder, making it a video DVD. And your narration audio file could be repeated in several languages -- one file for each -- and included in the data DVD. Then when you -- or whoever -- are making video DVDs from all this data, you download narration file 1 for the video DVD in language 1, narration file 2 for the DVD in language 2 and so on...
