Linux - Change Domain Name

Hello, I know absolutely nothing about Linux don't even know what it looks like. i've been asked to change the domain name its been assigned in Active Directory Users and Computers. The Linux box is setup and running under VMWare Server.

Can someone tell me how I can remove it from the domain then rejoin it under a different name and if that will cause any issues?

Also if you know any good visual tutorials for Linux it would be appreciated.