Definitely using stop, not pause and definitely within MC.
In the library view -> movies, or Theater view (behaviour is the same), I select and click on a movie to play it. First time it all goes fine.
Click stop, the application reverts back to the previous view.
Choose the same movie and select it to play again. I get the explorer window showing the contents of the disc.
This is the same whether I use the native tools, or if I have daemon tools installed. This is on a clean install of win 11 but it's always done it for me, from <v30 and win10 I believe.
If I choose play from the drives and devices when the disc is mounted it works, and I think I can navigate to a sub menu within theater view to play the mounted disc as well, but it would be nice to be able to not have to remember and to just select the movie from the library.