how to configure a domain controller

You need to configure this in samba. I could go on and on about how to configure samba for this, but you would be better advised to look at www.samba.org for documentation. Samba is probably already on your system if you did a default installation. If not you can get it off of your install CDs or download a newer version from samba's web site. Your config file is /etc/samba/smb.conf. In there you can set it as a domain controller and configure other properties.

Good luck.

While you can create a Linux domain controller for a Win2K based domain, it will NOT operate the same as a Win2K domain controller because it lacks Active Directory.

in honor to timwalsh?s answer:
A Linux DC will look and work like an NT4 PDC to other Domain Members. A full w2k-domain is not posssible! However, you can use samba with a LDAP-SAM (but that?s not the same!).