Graphic Issues and iTunes Problem

[Thopedam]

Hello guys... now i try to describe my problem:
I got some Mac OSX games and i try to start them, i came mostly into the menu, but if i try to play the game crashes everytime. so i think my graphics card got a problem or i dont know whats wrong

Other Problem:

I updated my Kalyway 10.5.2 up to 10.5.5 everything fine, BUT if i want to go into the store of itunes 8.1 (i updated in 10.5.2 there everything works) or itunes do anything with it (cover loading or sth like that) it crashes.
thx for advise

Specs:

Mac OSX Kalyway 10.5.5
ATi Radeon HD2600 xt pcie 512mb
ASRock AlifeXFire-eSata2 (SB600)
AMD Athlon 64 X2 Dual Core 5000+
i dont know what kernel, but in the install there was anything with 9.2.0 sleep im not quiet sure sry...