...management system? I want to create a web site for a small non-profit. The site needs to manage documents, user registrations, and allow easy update of information.

Joomla is your best option.

What is Joomla! ?
Joomla! is an award-winning Content Management System (CMS) that will help you build websites and other powerful online applications. Best of all, Joomla! is an open source solution that is freely available to everybody.

VIsit http://www.joomlacrib.com or joomla.org to learn more.

Everyone seems to rave about drupal. I have never used it myself but it is used on the site threadwatch.org

drupal.org

Drupal is good because its capability and most importantly it's free. However, its UI are very very confusing. At least one of Yahoo! sites use Drupal, though.

Mambo, now Joomla is best open source content management system as per your requirement. It is easy to manage documents, user registrations and all.It uses technologies PHP,MYSQL.Below are the urls related to mambo.
http://www.mamboserver.com
http://www.mamboforge.net

There are quite a lot of content management systems to choose from. I would like to point you to CMS Matrix ( http://www.cmsmatrix.org ) for a very comprehensive list of CMS's complete with a search tool. If you would like to preview how a CMS behaves with demos, try Open Source CMS ( http://www.opensourcecms.org ).

Hi, This post of mine is very beneficial and informative, however there are some specific facts or information that I require. If anyone can help me in this matter then please send me a private message. Best Regards,

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Hi, this post is very informative; however I would like some specific information. If someone can help me then please send me a private message. Best Regards,

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