You will probably get other answers. But, Premier Elements is first and foremost aimed at making videos from camera clips. It often can't manipulate videos from DVDs, capture cards or other miscellaneous sources. Other specialty programs may be able to, but I don't know which ones they are.
First, this sounds like a commercial DVD. If that's the case, you may be dealing with some copy protection issues that we can't help you with.
That said, how are you getting the video from the disc to your computer? Ideally you should put the disc in your disc drive and then use Add Media/From DVD Camera or Computer Drive to open the Video Importer, which will copy your video to your hard drive and add it to your project.
If you're using another method -- such as just copying VOB files from the disc to your computer -- you may not be copying the correct files.
Thanks for your response. The VOB files were pulled from a non-protected disc. The files originally came from a commercial disc, but were cleansed of copy protection years ago by means of 1ClickDVDPro. The original protected disc had a menu to select the appropriate audio track, but this disappeared in the copy. But I find that I am left with video files that have two embedded audio files. Although I can stifle the unwanted track with DVD player menus, I simply wanted to know why PE 13 seems only to recognize one of the tracks but not the other, and it does not afford a means to delete the wanted track, since it does not show the track that is wanted. If both tracks are embedded, how come the program only picks up one? Also, the VOB files are stored on a hard drive, to which they were ripped from the sanitized DVD.
That's going to be a problem then. 1ClickDVDPro is the wild card here. I don't know how it's affected the original disc files or how to control which one Premiere Elements reads.