The Service is meant for headerless servers (ones without monitors, etc.) so the MediaMonkey Server is available for clients on startup of the PC with the Service (without logging into Windows). The MediaMonkey Server as Service should be able to act as DLNA server and do wifi sync with MMA on Android. For most users the Service is not needed (as they can just run MediaMonkey itself).

Library sharing, if on, runs when MMW is running. If service is installed, when mmw shuts down it (service) starts up. Then when MMW starts up the service shuts down.
MMW does a lot of stuff that the service doesn't do ... in fact i believe the only thing the service does is stream.

What is the difference between these two, and can one run when mediaMonkey is not running as a service in Windows?