Gardenknowm has pretty much summed it all up. Make sure you put the thermom at plant level.. that way you'll know how far you can bring that light down to. And test it with your hand just to be sure. I would recommend using a high output energy saving compact flouro during the early stages of veg. That way you save on electricity, bulb life, cooling concerns etc etc. Plus node spacing and secondary growth is amazing.
I use a 48w (240w equiv) cfl, 5000k. Watering twice a week (once with half strength nutes). I personally don't like touching or digging around in the soil. Probably no merit to this theory but who knows what bacteria/mould I might spread to the soil from my hands.