oh, you can't vent... CFL it is
do not go greater than 65 watt CFL, they are not as efficient as their smaller counterparts, and the 100watt ones have HUGE built in ballasts that can be kind of annoying to set up, and they get hot too....
do 42 watters.... 2700 lumens per bulb, you'll need at least 18. 18 x 2700 = 45900; 45900/16sqrf = 3037.
mj needs at least 3000 per square foot to grow, but that's pathetic, the sun has 10000 per square foot in summer...
for best results get round 25-30....
you don't need to start out that big... seedlings do not have enough surface area in their leaves to absorb all the light...
if that seems like a lot, there's people that have 60+ CFL's in a single closet grow, that's to get very nice yields....
google different CFL grows here, and see which one is best suited for you....
there's a very VERY thorough tutorial in the CFL growing subsection, it's around 20 pages long... it's very detailed, step by step guide to a closet grow.... you WILL learn everything you need from there....
i read it... you should too....