Win 2000 server login issues

I was given this computer from a friend who bought a group of items from an auction in which he received this computer which was a dell dimension 2400 (windows 2000 server on it). He doesnt mess with computers so he gave it to me to "play" with. I am trying to "crack" it so i dont have to reload windows (seems like the Dell license never works with a original windows cd) No CD's came with this. I found software to clear the password but I cannot change the server I log into. How can I (or can I)change the server location somehow without logging in? If I can change the server I log into or create a new one then I can use this software with out having to reload a new windows OS on it. ANy advice would be greatly appreciated.