English subtitles for movies when watching them on HDD

I had just downloaded the Girl Who Played With Fire and The Girl With the Dragon Tattoo. I have an external HDD that I have plugged into my HDTV so I can watch the MKV movie files. The movies of course aren’t in English so I need a way to have subtitles enabled when watching the movies from the HDD. I was able to get the subtitles enabled when I burned the movies to DVD’s and to watch them on my DVD player.
Answer #1
use ‘mkvmerge GUI’
Answer #2
Your HDTV should have a menu to enable/disable the subtitles. If you post full details or the link to specs, it can be checked out
IF it doesn’t, and it doesn’t support either internal or external subtitles, you can use MKVmerge GUI (to make an external into internal) or MKVcleaver (better than MKVextract GUI – to make it external) and try
But…please note that MKVtoolnix higher than v4.0 may not work
You will find info about them in my Help Guide (link in my signature)
Good luck