Ain't this the biggest tease in God of War?

just played the game, i'm up to the part right before i fight ares, and guess what, the game starts skipping and when i'm heading up the stairs before i fight ares, i come to a dead end and when i loop around it i fall down and die in some dark pit, what the heck is going on here, i checked my disc and only has a small scratch, nothing major, what the heck can i do, go to the tape store and rent it out just to beat the game!?! i made it this far and now i gotta stop for now! grrr hate these cd's