Setting up a home server

Hey guys,

I'm new to this forum so i am not sure whether i posted this question in the right area, anyway here i go;

Does anyone know about a way to set a home server to store media and files as well as time machine backups. In my house we have three macs and it is always annoying having to share files such as songs or movies. Recently i have had to look at a time machine back up system so i though i would kill two birds with the one stone so to speak. Anyone ventured into this area before? I have seen the Drobo but not sure whether that is any good or not. I also want to set up the server so that i can host files on it and access them from another computer over the internet while allowing anyone on the intranet to also access them.

Cheers,
Francis

P.S. I also though of another question. Is it a good idea to install Mac OS X server software to administer it and set it up?