|1. You're running Vista.|
2. On a more serious note, either you do not have Direct 3D installed (unlikely since it comes with every windows OS since the 9x days), or your video card does not support the D3D function it is trying to perform, ie, buy a decent video card.
And we need to know what kind of video card you are currently using, D3D errors have nothing to do with CPU specs.
PowerMac 9600(1 ghz G4)
ATi 9200 PCI