I assume you can watch everything in the DVD player.
Another program you can try is Ulead DVD Movie Factory 2.
They have a trial that you can download.
DMF2 looks for the Video_TS folder and reads all the VOBs (it does not work with DVD with AC3 audio like the commercial movies).
After you read it, you can create new DVD folders and if you want a new DVD image for burning.
However, you should not expect suppot from Ulead.