So live recordings.
Well, that one is mostly up to you how you want to organize these.
Personally, I have a separate library of the type “Movies” (agent “Plex Movies”) for this type of content.
If you can find your disc over on TheMovieDB.org, you can save some manual labour by using the exact title and release date (or maybe even the TMDB ID number to ensure a perfect match).
Otherwise you’ll have to type in all the metadata yourself. (Be sure to explicitly “unmatch” the item before doing so. This will prevent future attempts of Plex to match the video to some unrelated movie with a similar title.)
Using a “Movies”-type of library enables you to add bonus content to the main concert just like you would add movie extras and local poster art. https://support.plex.tv/articles/local-files-for-trailers-and-extras/
This wouldn’t be possible if you used an “Other Videos”-type of library.
Here is a concert which has a record on TMDB. Main advantage is that the “actor” information is present.
I’ve added the bonus content from the disc as local extras.
Combined with manually created collections in my music library, it creates a quite usable result:
