Hey bro, well those are good interesting questions, that a newb should always know.

First of all the space is alright, for the amound of plants you are planing to grow. The aluminum foil is not a bad idea it has worked for me perfectly, but youll get tons of different opinions about that one.

Second the lighting if you are willing to use fluro bulbs, you can use spring kind, those are the ones that youll find with a higher wattage, if you are planning into using 2, try to find 2 55 watts, one cold light and one warm light. You wont need a fan it wont get too hot, fans are good for HPS or MH or MV systems, also for incandecent lights, but fluros dosnt get that hot at all.

if the space is 4 foot height the lights would be ok if they are set up at the top of it, you dont need chains for this this kind of bulbs they are not heavy at all