I am missing the DAR file, but have a video_TS folder, an audio_TS folder and an SPREPARE.SPSS file. Is there a way to recreate the DVD with just these folders?
If you just want to make another DVD, use a DVD burning program such as Imgburn to burn the video_ts folder (and the audio_ts folder if you are really pedantic) to a blank DVD. Forget about the SPSS file.
If you want to reconstruct the project so you can make changes - sorry.
EDIT
You can probably use DVDA to do it too. Just select "burn from a previously prepared folder".
"(and the audio_ts folder if you are really pedantic)"
The AUDIO_TS folder is part of the DVD spec, even though no one uses it (it was called HD-Audio). Some players strictly follow the spec and won't play a video DVD without the AUDIO_TS folder.