I'm not sure exactly what you are trying to do. Indoor ambient light is nothing more than the light provided by whatever fixtures are usually in the room. If that is what you are trying to do, then by all means avoid overhead flourescent lighting and install wall-mounted light fixtures.
If you're asking about indoor lighting using windows, then bigger is better (you can always make them smaller). North facing windows provide similar light any time of the day or year, but north, south, and west windows are constantly changing when the sun is out.
Thanks Chuck, yes I want to use only the light provided by the sun. Windows, windows, windows. Would it be necessary to use sky lights? Thanks Kim