Ask YC: what CMS do you use?
can u suggest powerful content management system (Joomla, Drupal, Pligg etc.). yes, it has to be open source.
You should not limit your available tools. And of course, different tools work better for different jobs.
For most things, I prefer ExpressionEngine.
It's open source and the developers are quite helpful on the mailing list. Documentation is fairly decent with many howto guides for newcomers. Being a web-developer for over 7 years I highly recommend it.
You're wasting your time with this kind of post.