I would assume you just start with start_server.py or the gui version, start_server_gui, yes.
They both (just had a quick look) seem pretty easy to use and the non-gui seems to have some documentation which is good for OpenRPG
I saw how to register easily enough but I am not sure how you go about changing the HTML file that is displayed when someone logs on to your server. It's probably a file somewhere. The rest of it is mostly controls for kicking off abusive or dead users.
Those files come with the standard OpenRPG install / set of files.