Apple mentions that the Mini makes a nice server - in fact it easily meets the requirements for SL Server (providing of course, you dont intend to use it for anything that would require dual ethernet interfaces).
Snow Leopard Server is also an OS, yes. However, I am getting the impression that Snow Leopard Server is not for you. The standard version of OSX is more than capable for most standard server functions, and basically if you're not certain you need the Server version, it's probably better if you don't have it.
I do need the extra functionality, i am just deciding whether to just install it on my imac and use it as a server and occasional computer, or have a seperate mac mini.
OSX Server doesn't require much of a computer unless you're using the Server for something specific that is bogging down the machine. It requires 2gb of RAM as opposed to standard Snow Leopard's 1gb, but that's really the only significant difference.
ok thanks for the help. One more thing, the link you sent me; i'm using this for my home, so do you think they would figure it out when i lie about my "business"?