Does anyone know how to get a dvdr dis to play on other dvd players?

I am working with a magnavox dvd player/recorder mwr 10D6 and am using it to record church services by camera. After I finish recording the service on a blank dvdr disc, I remove it from the player and put it in my laptop afterwards, and I get a message saying the disc is blank (which is something I see as odd because it has video burned to it). The remote for this player has no finalize button. Does anyone know how to fix this?