Is there anyway to rig an avatar in such a way that the everything below the leg bones don't actually do anything to the model. I want to have all the hand and arm motions, but no leg movements. All without having to do custom animations. the skeleton would also be humanoid, just no working legs. 

Also whats an easy way to add shading and highlights to a material without hand painting it or using shaders (since i want to add shading to a place that has no geometry)