@ LaurieA: The OP is using PP 2010. 

Depth Mapping will kill your renders, they are memory intensive.  Switch to raytracing in your lights. 

Because you are using gamma correction in your render settings, light intensities show be down played, never intensified, unless there is an absolute need for effects.  Defaults lights, as mentioned, are a no-no.  They are not set to raytracing, as you can see in their properties. 

Use the manual feature for the render settings, you have more control over your final renders than just using the sliders.  And you can also activate IDL. 

My recommendation, delete all default lights and create 2 new ones.  One should be infinite, 75% intensity, white, raytrace shadows, keep everything as shown.  The second light should be an IBL, white (no image attached), 10 - 15% intensity, Ambient Occlusion on, no shadows.  Render and see what it gets you.  I have a suspicion that the textures are very screwy.