With an area that small I'd say soils probably gonna be easier, or coco. It depends on what style of grow u want to do, if you want to do a SOG and have a seperate section for clones/veg, you can use an area of 3X2 for your bloom section. 6 square feet you can have about 6 small plants (1-2 gallon soil/coco), 3 medium sized (3-4 gallons), or 1 full sized (> 3.5 ft). The other space can be sectioned off using light proof barrier and turned into a veg/ clone chamber. As far as lights for veg some CFLs would work great. Id say 4 X 23 watts for veg section. For flower, a 400 watt HPS would work well, but heat may be a problem. If you cant exhaust hot air out of the closet and out of the room, you may want to stick to CFLs for the flower section too. Use a mix of 3:1 warm white to cool white (2700K / 5000K). I'd say at least 5 42 watters, the more the better though. If you can afford it, adding a red LED or mostly red in the flower section will help too.