That's not so easy. Selectable DVD subs cannot be saved as an editable text file. DVD subs are basically a video stream. There are programs that can convert them to a text file but it works on a text recognition principle, similarly to converting a scanned page into an editable text file.

As to the SRT only problem, there are free programs that convert between different subtitle formats, so it shouldn't be much of a problem to use whatever subs you have and then simply convert them.

PS: MSycamore, could you please check out my ROTJ DeEd thread and tell me what you think about the subs in my latest sample video?