So this is more a problem that perhaps Roon should look into resolving with this information, as mp3tag is actually displaying the details correctly. I am struggling to actually understand why Roon is even grouping these tracks together, since they have a different Album title. That alone should force it to consider them as separate albums, even if the files remain in the same folder.
I do understand your frustration, but I think I would go about dealing with these discs in a different way to avoid this pain.
A few ways I might consider (the first would be most likely what I would choose for my library);
Set the AlbumArtist as "Various Artists" and the Album as "Niram/Primpoojari" - and set the Artist as needed for each track. I'd also set the Compilation flag as 1 as this helps some players deal with mixed albums. I know you are considering this as two albums on one disc, but really this is just a mixed release - and hence the dual title I am suggesting.
Split the disc titles as if they were two separate releases, with the first 7 tracks as Album "Niram" and the other 6 tracks as another Album "Prempoojari" and the rest of the data remaining as you have listed. This is most likely going to accomplish what you seem to be looking for, but I'm not sure if Roon will display this correctly based on your current feedback.
Set the AlbumArtist as "Vidyasagar; Uttam Singh" and the Album as "Niram/Primpoojari", without setting this as a compilation disc. Depending on the player, it may accept a multi AlbumArtist field with the "; " separator (or maybe some other character). From what you have here, it seems highly unlikely that Roon will support it.
If that roon puts together all files from 1 folder to be also just 1 album, then I still don't understand why the folder structure could not be adapted accordingly, like 1 folder for the 1st album, a 2nd for the 2nd album. And 1 folder level above the accumulated name - which could mean that an extra folder level has to be added.
It seems that such albums get the ALBUMARTIST name of the music director "Vidyasagar" and "Uttam Singh" not the usual "Various Artists" for the many different ARTIST names per song.
But why roon combines them to 1 album remains obscure.
These ate 2 completely different albums/movies from 2 different music directors(Vidyasagar is the music director for Niram and Uttam Singn is the music director for Prempoojari) with many different track artists (The tracks aka songs are sung but different people/singers.
Indian Film music widely knowa as Bollywood. The film has songs sung by the characters.
Songs are composed by music directors (Vidyasagar/Uttam Sing) and are sung by singers (Yesudas etc). Two or three movies/albums go into a single disc.
Hence this first option doesnt work. I tried in roon but did not get the desired outcome
I'm wondering what he disc title is? Is ir %title%, if yes that should be the name of the song. isn't it?
I tried this with separator (, ; and /), still it combines all two as single disk.
That is not quite right.
1st album/movie has tracks from 1 to 7 composed by Vidyasagar and sung by various singers
2nd album/movie has tracks from 8 to 13 composed by Uttam Singh and sung by various singers
Yes, however there are documented official releases of each of these albums that were separate, unique discs. (See the above references to them that @LyricsLover posted). So these combined discs you have are not albums in the traditional sense, but are more like samplers or what I suggested as compilations.
I guess the reality here is that between this feedback from Roon, mp3tag, and several experienced users offering their help and suggestions here, there must be something you can work with. Clearly you are working outside of the established conventions, which is completely common with music libraries. They can often be highly personal and there is no perfect method for all. But there isn’t anything more I can offer than I have already put forward.
