Hi,
I'm also trying to find a good configuration to have the best performances possible, here's my computer's specs :

OS: Windows 8 64-bit
Memory: 8192MB RAM
Processor: Intel(R) Core(TM) i5-4590 CPU @ 3.30GHz (4 CPUs), Socket 1150, 6mb cache memory
Graphics: GeForce GTX 750 Ti, 2048 MB
Emulator: PCSX2 1.2.1 (r5875)

I used ImgBurn to have a .iso of the game (I have an original copy of the game), using directly the CD wasn't working.

Thanks !