PHP Content Management System

I am going to be needing a full backend for a website content management system. I will need a control panel to be able to post articles (in html format) with an attached category. I should be able to have complete control over the categories including adding new ones, editing existing ones and deleting ones I no longer need. I would also like to be able to move articles from one category to another. The content that is being stored will need to be displayed on various pages and I would like the posts or articles to be tied into a forum so that there can be a "Comments" link at the bottom. The content management system should give me complete control over the site, including the display of a set number of "featured articles" on the front page (with a picture next to it) as well as adding various links and other content to the different parts of the site.