I`ve been having a play around with a really good free open source cms script called Subrion. It has all the usual required tools to run a CMS based website.
Main url: http://www.subrion.com/
Demo: http://demo.subrion.org/
If you install it and try it out, let me know how you get on.
Subrion is a free open source content management system.It's written in PHP 5 and utilizes MySQL database. Subrion CMS can be easily integrated into your current website or used as a stand-alone powerful platform.
It's extremely flexible and scalable php system that stands for a content management framework. The strongest community behind the Subrion project provides all users with extra functionality and friendly help through user forums.
Main url: http://www.subrion.com/
Demo: http://demo.subrion.org/
If you install it and try it out, let me know how you get on.