What is the "best" free CMS for my needs? [closed]

Question

I have the task to build a web-site for a smaller non-profit organization. I have a bit experience with ASP.NET but because ASP.NET hosting is rather expensive here in germany (we will also need a lot of webspace and traffic) and aslo because there are quite a hughe list of features I think I should go with a PHP/MySQL based CMS (correct me if I am wrong). The question is wich one? There are are so many free CMSs out there. If I tell you what I need, can you tell me what would be a good choice?

Here are my requirement (sorted by priority):

1. Ease of use (installation, configuration, maintainance) for me who builds the site but also for the members of the organisation they must be able to easily change the the content of some main pages, add supages, add a new mailinglist upload a file to the repository etc.
2. A membership/role management system. Based on the role of a member access to certain subpages, subforums or folders in the file management system etc. must be restricted. Only certain roles must be allowed to add new mailinglists or moderate the forum.
3. A mailingsystem that allows me or the members of the organistation to add new adresses, maillinglists or newsletters.
4. A file management system. Members should be able to upload arbitary files on the server and browse them via a web frontent. Access to folder should be restrictable based on the member rights.
5. A pulbic forum with private subforums.
6. Localization. As much as possible of the final site (if not everything) that is presented to the visitor of the site as well as to the members who maintain the site should be presented in german.
7. Good control over design/look and feel of the overall site. I should have good control over how I want the site to look like.
8. A lively community with enough momentum to find ressources and help when I am lost.
9. Extensibility. In case there are some smaller features missing or f the behavior of an existing feature is not quite the way I want it, it would be cool to easily add it myself.

Answer 1

As mentioned by others, Joomla might be a good option for you, although Wordpress may also work (and it's easier). However, I highly recommend that you check out OpenSourceCMS.com, which hosts demos for many of the free and open source CMS's, blogs, forums, shopping carts, etc. For most of them, you can try out both the admin and the frontend. Spend some time looking them over and then when you find some that you like, investigate them further by going to their websites.

Answer 2

Concrete5 is a new Content management system that is excellent. Easily themable, user friendly, great little dashboard for management

and it's open source