Well the green LED fan is integrated into the cpu heatsink. It cannot be turned off unless you do some modding to the fan. Or you could just replace it with one that doesn't light up.
That green LED fan is the only aesthetic light in the case. The blue lights you see are the motherboard lights and the power LED. My crappy phone camera makes them look much brighter than they really are. Even the green fan is not overly bright. I also have my PC set up in my bedroom and if I ever leave my system on overnight it does not bother me much.