hi, im a complete n00b to hackingtoshing, i have no idea where to start, i would like to run the apple osx on my laptop, but am so confused at which one whats so ever.

my laptop - Processor: Intel® Core 2 Duo T9300 (6M Cache, 800 MHz FSB)
processor speed: 2.50 Ghz

Operating system: Windows 7 Professional 64-bit
4GB DDR2 667Mhz (2x2GB)
320GB HARD DISK DRIVE SATA 5400rpm
NVIDIA GeForce 8600M GT with 256MB dedicated RAM

i was wondering which os/ how to install it? and if i should dual boot it and keep windows 7 on it as well? cheers Ali