Converting a blue ray download to dvd?

[Loki's]

I'm going to paint myself as completely tech dumb right now but I need some help. I downloaded a few movies and all but two work fine. The two that don't, the video lags/jumps but the audio stays the same (I've tried them on KMPlayer and VLC) The only difference I can see between the files that work and the files that don't is that the ones that don't work are BluRayRip while the others are DVDRips. Since I have at the moment, a reaaally crappy, old computer I'm wondering if that's the reason, like if the higher quality doesn't work on old computer models.

Is there any program that will convert them, like is that possible or do I need to find DVDRip files to download?

Thank you in advance

 

[papeche]

the computer may be choking on the bitrate. convert it to a lower bitrate, I bet that would fix it right away.