Advice for Video Library

I bought the WD TL Live media player, and i’m quite happy with it. Although there are some minors problems that make the experience perfect

  1. First i just decrypted some dvd’s on an external HD using the VOB format. If i have 1 movie on the HD and the files are called VTS_01_0, VTS_01_1, … and so on there is no problem

But when i add a 2nd movie (ofcourse in a different folder) it still causes problems as those files are also called VTS_01-0, 1, 2 …

And when i try to rename the VTS to the actual movie name, the WD TV Live is unable to find the subtitles

  1. So i decide to use the Handbrake program and convert the files to mkv, which reduces the file size without quality loss

And i can add subtitles as well

But the problem here is that my subtitles are completly white. There is no black border. In 80% of a movie its not a problem, but when the movie scene is white, you are unable to see the subtiles (or part of them)

This must also be related to the Media player, since VLC player on my computer displays the same file + subtitles with a black border

So i would really like to know: what is the best format for my DVD movies so i can watch then without any hassle and the subtitles are readable