Your post didn't explain much. Hundreds of things can go wrong copying DVD formats. For starters, my DVD player will only accept DVD-R, and doesn't like DVD-RW, DVD+R or DVD+RW discs. Your DVD player is probably more recent and should accept more formats, but you never know.
You didn't say if it was home movies or Hollywood movies that have copy protection. You can also have technical issues with bad sectors, over-sizing, on top of DRM issues. You can write a book about problems on DVD burning.
But check first to see if the final product DVD movie will replay on your PC. If you have successfully burned a DVD that will play on other players, then it might just be your DVD player, try a DVD-R format disc, to see if it works. Might be worth a try. But there are so many other things that can go wrong burning DVDs, it's hard to say.