discovering a server configuration

Okay, I have a question for the experts here. I have a windows 2000 server and several windows 98 and windows xp machines. I am not sure how the windows 2000 server was configured. I have no documentation. What I need to know is how do I identify the different parts of the windows 2000 server (DHCP, DNS, IIS server, the users that log in, etc.). I am not sure where to start or what to look for, other than a few basics such as the admin console.