Well ... firstly, you can avoid Korean subtitles by not downloading English TV Shows from Korea. :)
That said, and without knowing what OS you're using, mkvtoolnix comes in a variety of different distributions and has everything you need to remux (i.e., repackage the mkv without recoding the video or audio tracks, and stripping out any tracks you don't want -- takes a minute or two per file, generally), and edit the track headers (i.e., reassign default/forced track tags within the mkv -- takes a few seconds per file). In fact, Plex member OrionShock has even provided a primer on mkvtoolnix in the Plex wiki, here...
The audio/subs tracks in your files are presented in the PMS Media Manager (a.k.a. Plex/Web) dropdowns for each individual file.
Finally, as for playing foreign audio with English subs, the playback end of things is dependent on the client device -- and you don't mention what you use to play video served by PMS. Many clients will let you select which tracks to use in multi-track MKVs, either at the start of playback or on the fly. Yes, you can set preferred audio/subs on the server, but that is primarily honored by the PMS /web client ... other clients do what they will with the video you send it.
Edit: As a final note, this is not really a feature request...
Also please remember that while plex is awesome, it is not telepatic. If you give it files that are poorly managed, you will get poorly managed playback (ie: Garbage In/ Garbage Out)
Thank you so much for the replies & advice guys.
Just found the media drop-downs! By actually clicking in to view the metadata section first
(I was clicking directly into the edit mode where they are correctly not displayed) :wacko: derp.
I'll definitely check out the mkvtoolnix,
I was worried that it was gonna be a complete mess and hours of re-encoding,
but if its that easy I'm happy to work through my media.
I agree 100% about the trash. I'm always on top of my media organisation,
but lack knowledge when it comes to encoding & packaging
so I go with whatever format was available to d/l.
Even if they are from Korea. :P
Also, I'm happy if an admin/mod wants to move this to the server support forum.
Thanks Again!
there is also a program that can edit the metadata in bulk if you have a bunch of files that are all the same layout.
http://code.google.com/p/jmkvpropedit/
IE if you have a whole set of files that are only english audio and english subtitle, then you can IN BULK with this tool set those values all at the same time.
If you have a set of files that are dual audio / subtitle & the english track is always in the same spot ( either first or second IN ALL files) then you can set them accordingly all at the same time.
Early 2021 clean-up: duplicate