dvd problem help pls!!

hello,
im having some problems on the new purchased dvd player, grundig gdp 2750 some of my media dvd-r like philips, it reads them good but all of my other medias doesnt read them good, the picture it moves very fast, and all of them become out of sync, i had a dvd player called GRAETZ which was very good, all media reads them perfect, but i dont know how its not working anymore, the disc wont turn. any help pls what kind of dvd player should i buy to read all media dvd-r, without any problems, thanks