I opened one of the OC areas to see what settings they defined for realistic firelight (torches, candles, fireplaces, etc). Based on that, these are the settings I am using for basic light sources:
Behavior
Shadows
You may also want to nudge the colors just a bit towards red and orange. Not to the point of being overpowering, but just enough that it's not plain white and gives a subtle red/orange undertone.
Nwn2toolset posted this great tutorial on using lights by Geethree. It covers shadows, lerp and some other great items that you might have missed on your first pass through the lighting options.
Check it out here:
http://www.nwn2toolset.dayjo.org/ToolsetTuts/blueprints/lights/light.htm...