RE: difference in prop types
Depending on the drag factor of the airframe the engine is to be used in, I prop about 700-1500 RPM less (static) than the maximum RPM of the engine.
If the engine is to be installed in a WW-I biplane start W/the smaller spec'ed props. If it's going into a P-51 Mustang, go W/the larger spec'ed props.