Dual boot Windows 7 + Mac OSX 10.x.x

Hello, which one would suit me best, and what "number" like 10.5.7 or so on, iAKTOS, iDeneb or so on? heres my specs:

Operating System
MS Windows 7 Home Premium 32-bit SP1
CPU
Intel Core 2 Duo E8400 @ 3.00GHz
Wolfdale 45nm Technology
RAM
2.0GB Single-Channel DDR2 @ 401MHz (5-5-5-18)
Motherboard
MICRO-STAR INTERNATIONAL CO.,LTD MS-7519 (CPU 1)
Graphics
AL1916 (1280x1024@60Hz)
AL1916 (1280x1024@60Hz)
NVIDIA GeForce GT 220
Hard Drives
488GB SAMSUNG SAMSUNG HD502IJ ATA Device (SATA)
Optical Drives
ATAPI iHAS124 Y ATA Device
Audio
USB PnP Sound Device
Chipset
Intel Å45/P43/G45/G43

Dual boot Windows 7 + Mac OSX 10.x.x - which one?