DVD's won't play on portable

I have backed up many movies (I have 3 children and it makes for less fighting!) lol. I can play the movies on every dvd player with no problems. Just got the kids portable players for Christmas. they are Dolby surround Venturer’s. The movies play half way thru and then get all distorted. The original dvd plays fine. (The burned ones do play fine on the dvd player on the tv and on my pc.) What can I do?

Welcome to this forum of CDFreaks, this problem accurs when the portable player is not cmpatable with format of DVD have been made, try the stock DVD (Movie or Game) if still no luck then the portable is not made for this purpose or is defect.

Try DVD+R with bitsetting - maybe the player can “see” the disc as a DVD-Video disc - if it is a matter of compatibility.
But be prepared for bad news if the problem is a copyright issue - some players will refuse to play some copies even if they acept the disc format (plus or minus).
It can also be a tech prob, but if it plays the originals…the probabilities are low.