will this work for lighting?

ok i have 3 plants.

for veg. im using 2- 100W Cfls(one looks redish light and other blueish light)

after the veg cycle i was going to flower one or two plants with a 400 watt HPS(got this from my friend for free.)

is that good?

also when do i put them in the flowering stage? i was thinking like 12 inches was good for veg.

very good! alot better than some of the ppl here who flower with CFLs (bad choice). your veg cfl's are strong too - good stuff! since you said one is red and the other is blue, you probably have both flower and veg lights. you should use both of those when flowering too, let the sides of the plants get a nice dose of both spectrums of CFL while the tops get penetrated by the 400watt. you can wait however long you want to flower, but usually its best to do so when theyre small so they can double/triple in size. they have alot of vigor when they're small, but you can wait til theyre even 2-3 feet to flower and youll end up with 1-2oz/plant.