The problem could easily be something the matter with your playstation or the disc itself.
Playstation 2 is a pretty old system, and for it to load a game years ahead of the consoles creation graphic wise and on and on, is a little less than comprehensible. I would check the disc for any scratches, smudges, etc. and if it's perfectly fine then i'd assume it's you console having a problem loading the graphics and music onto it's old self.
As long as it's working, i'm not sure i see much of a problem.
But i do know waiting forever for a load is monotonous and horribly annoying, so i do hope this problem fixes itself seeing as there isn't mush you can do but upgrade what console you're using.
"i once killed an antelope, you should come over for dinner"