No, the 250w e40 is a self ballasting CFL. Which means all it needs is a plug on the end.
Most (decent) reflectors come with a female socket to hook up your ballast, when using a CFL just put a kettle lead in (PC power lead, you know the thing). If not, just attach a plug.
You only need a seperate ballast for HID bulbs (metal halide or high pressure sodium). For CFL it is just a lightbulb, any additional electronics required will be included. If you look at the picture of a CFL the base between the bulb elements and the screw fitting contains all you need.
From what I've read in this thread you have plenty of questions, this is the best place to come for answers
I would say that you could get away with only 1 250w blue CFL, personally. I veg using a single 65w 6400k CFL and have no problems at all. I own a 300w 6400k, however my experience has shown zero difference between plants vegged with lots of light and plants vegged with little, hence why I don't bother spending extra money on electric when it doesn't make any difference.
Wattage really starts to matter during flowering, later flowering in particular. Personally I have spent the last 8 months experimenting with indoor growing, looking at the effects of different light levels, feeds, etc to find what works best for me.