Just a few tips:

Change the "Map Size" on your light from 256 to 1024.

Use raytraced shadows, not depth mapped and set raytracing in your render settings.

NEVER, I repeat, NEVER use the auto render settings. They stink ;o).

And as other have said, learn how to use lighting and it will go a lot farther toward making your images look better. Have you tried IDL? It looks like you're using Poser 8.

Laurie