it kinda depends on how tall you want to let them grow... i'd say you could fit 4-6 in that space. alot more if you were going to do a SOG grow though.

As for the lights... everything you want to know is here: http://boards.cannabis.com/indoor-li...uch-light.html

I also suggest reading this one too: Text

something else..

for your ventaliation, do not put a fan on the in-take, you can just cut a whole for a passive intake and use a fan on the exhaust. You want your cabinet to have slightly negative air pressure, and thats how you accomplish that.

Having an in-take fan will not increase air flow at all (unless your intake was crazy small compared to the exhaust), all having an intake would do is give you equal air pressure.