OS X and Kubuntu join domain

Hello, I am looking to have an OS X and Kubuntu client join a Windows 2003 Server Domain using active directory. I have been searching and was wondering if anyone knows of any easy to understand instructions. Thus far I have been unable to find any, since I am new to both OS X and Linux altogether.

What would be the purpose of joining the domain? Do you want the domain users to be able to access resources (shared files) or do you want the domain users to be able to log in to these machines?

My main concern is that domain users could access the shared folders. I should note the OS X version is 10.4

A basic setup for Ubuntu: http://ubuntuforums.org/showthread.php?t=280702
You can skip the PAM configuration if you don't need the domain users logging in to the machine itself.