For that size, a mix of 6500k and 2700k CFLs, using the Y adaptors. I'd try to get 6-8 in there if possible. More 6500k for veg, and then more 2700k for flower.
Also, pick up a roll of mylar from a local grow shop. It's cheap, waterproof and will aid in light distribution. Buy some silver metallic tape at the hardware store where you grab the CFLs, and seal the joints with it.
A couple of small computer fans; one exhausting out near the top, and one blowing air in from the bottom should be all you need for air.
-spek