MKV Player is a handy utility that was designed in order to help you view MKV videos. It can be associated with your MKV files so you just need to double click the file to play it.
All basic functions like play, pause, seek, fullscreen are available.
You can also make your own playlists, save them, edit them.
If you have a large number of MKV files, you can use built in search to find your favorite from the list.