I'd like to make a website for a church, and I'd like members to be able to participate. Ideally it would have a photo gallery, a forum, and a news page, as well as the ability to post news to the front page and different categories easily.

I'd like the most flexible one possible. So far I'm leaning towards Drupal - any opinions?

Check out Joomla. See Home - Customized Church WebSite Solutions. for various features for the church community.

Drupal is easily the most flexible one from the ones I've tried. I prefer to have at least separate photo gallery (I use Zenphoto, it's great) but you can do it all in Drupal. I also prefer separate forums with phpBB (see www.poromenos.org for a Drupal installation and shameless self-promotion :P).