the laser will work a dam sight harder reading a dvd (film) than a game ,as far as i am aware !
the game will load from disc certain parts to play then load again where as the films need to read constantly ????? their in could be the problems with the discs ! ritek are cheap enough anyway i pay around £7 for 25 .
and i agree that you should play films on a dvd player and not your ps2 lol