Complete Growing Novice

Okay, so I've never grown before in my life and would like to try. I've read a few guides and have a couple questions to shoot out before its go time.

1). The area I plan to grow in is a tad small. 2 ft deep, 2ft wide and 2"5 high. Is it doable?

2). Its above a water heater. It doesn't get moldy or anything like that, but it does get warm. Is that a pro or a con?

3) If the first 2 questions get the green light, what are some strains that would grow nicely in said area. Something not very tall, but wide with decent gain.

1 Im not sure what kinda HPS/MH you could use, but i know CFL and Fluors would work.
2 I don't see a problem with it unless you can't control the heat inside your growbox then it could become a problem.
3 I've seen alot of people growing Lowrider here, seems like it stays pretty short and yeilds well.