Could someone check this for me, most of this stuff I don't understand O.o
The lighting makes your computer light up, obviously. The case...do what you want. AMD processors have slightly less power than Intel, but are the only thing you can get for a 600 dollar budget. Cooling, I would suggest this upgrade:

AMD cpu's seem to have cooling problems with stock fans. I do not know if the games you play need 2 or 4 cores, but I would go with the cheap quad AMD
The only RAM you can get is 4 GB with your budget, if you get the other upgrades im recommending. Video card...well...for a good one, your gonna have to bust the budget and get a 500 W PSU, unless you want to take a risk and go cheaper with a dual core processor. I can not help you with the HDs or motherboards.