An incandescent light is just a light like a regular old style light bulb, flood light, i.e.Incandescent is not the correct light to grow with.
Most folks use blue spectrum for veg, and red for flower. If the light your talking about is a metal halide light, then yes, that should be good to veg a couple of plants.You should probably add cfls all around these plants because 150 watts is not very powerful.This is an example of the type of cfl you want to use for veg.It says 6500k on it.
http://www.lampsplus.com/products/26-Watt-Daylight-6500K-CFL-Twist-ENERGY-STAR-Light-Bulb__35256.html This is the color temp of the light. K stands for kelvin.What this means is, the light is toward the blue end of the spectrum,like early spring and summer, when plants are in their vegetative state.For flower, you will need lights which are at the red end of the spectrum.The color temp for these cfls is 2700k.They are also called warm whites.They emulate the redder light you see in late summer and early fall, which is when the plant would flower outdoors.Generally, you will need a lot of cfl's to ensure good light penetration.