difference between Jap DC and Aus DC. Need help!!

What is the difference? Is there a difference in playing some
backup CDs? Because I played Sword of Berserk (Need boot disc)
on Jap DC and all the movies play smoothly, but when I play this
game on Aus DC, The first part of the movie where it says 'EIDOS'
does not run smoothly, and also just before the game when they
show the big sword does not run smoothly, also the sounds does
not flow.
Is it because of the difference between Jap DC and Aus DC lens or
the motor?? Please help, I am very curious..