Because nobody seems to know the answer, i answer myself in this case.
I perchased the WD Elements Play, hoping he would play the files.
I ripped a dvd and copied the Vob, Ifo and Bup -files to the drive, all putted in a video_ts file.
I navigated to the video_ts file and opened it but the player did not show the movie.
A quick search on Google learned that i may not open the video_ts file but have to navigate to it and when i see this file, i have to push the play button.
So i went back to the tv and this way, it worked.
I have tried with a iso file and it works to, all with subtitles.
1) rip your movie with Dvdshrink to a folder
2)create a folder with the movietitle and copy video_ts and audio_ts to your "Elements Play" drive .
3)navigate to video_ts folder and hit "play".
For ripping to iso, you select "iso" instead of "folder " at the backup menu in Dvdshrink.