If you have ANY possibility of getting caught over lets say 3-4 months from now, do not grow; especially if your parents are around, it's a 10 year felony(minimum), and they could lose their house over it. Not that you are, but a lot of burned out kids get on this site and think growing "iz sooo cool!" until their mommy finds it and screws up their lives. In short, think about it fully before you do it.
As far as lights go, any low watt MH or HPS would do fine in a box that size, you just need an intake and exhaust fans pushing from one side of box to the other. 1 plant will probably be a dissapointment, but great way to learn about growing, one plant isn't going to pay for its power consumption, fertilizer, pots, soil, lights, with fat buds Just think about how your 'rents will react to finding it.

I dont mean to lecture you or anything, I just hate to see peoples lives get messed up over this stuff...