Need a CMS ECM system... HELP

[Christopher Matthews]

Hi:

I am in need of a CMS/ECM system. Open source is the way for me. I currently have a PHP set up which allows me to upload files that people can pull down and look at later.

Im using a fiat to pull a cement truck!

I need to have specific user accounts and roles, I need to have version control, and I need to have the ability for my users to post comments to the versions which are posted.

Im looking for a software that installs like most PHP aplets do, browse to a config file, create a MySql db, make minor changes and drive on.

Does anyone know of a software which is open source that will do this?

Thanks in advance for any help you can offer.