This yet another post of how to start OpenOffice as headless Service:
After you have installed your OpenOffice.
navigate to the executables directory. this is under:
and type the following command:
soffice -headless -accept="socket,host=127.0.0.1,port=8100;urp;StarOffice.ServiceManager;" -nofirststartwizard
For More information regarding this topic refer to the following links