I'm going with what I think may be the simplist solution .
Download & install VLC media player .
These are the reasons .
I think your OS probably lacks the codecs for Jet Audio media player
to play DVD video files.
VLC has it's own codecs in its Program Files folder so doesn't depend on Windows codecs.
If VLC does play the video then the problem is not in your MSI DVD RW drive
or how you have cable select ,master , & slave set for the drive or drives.
Link for the VLC web site:
I also suggest trying several DVDs especially commercial ones in both players .
Some burned(writeable) ones too if you have some . Since writeable DVDs can vary so much depending on many factors you always need to test with a commercial movie DVD when having problems.
BTW: I'm not as old as you especially depending on which end of septuagenarian you are on . I will soon be 60 .
If there is some kid in your church that is known to be a computer whiz use him or her. Most of them started using computers some way before that could walk .