Honestly, if you are considering drupal and dolphin, you might want to check out joomla as well. I like joomla a little more than drupal. I do run a couple drupal site's as well. One is

http://ubuntu-georgia.org you can make it look how you and, but I like the administration, and the plethora of available components for joomla. It's code base is from mambo server.

Just my 2 cents.