You probably need some kind of content management. The reason we say this is because the best sites on the web, and the ones that generate the most traffic are the ones that regularly add and change their content.

For most sites we use the Wordpress system for content management. It's by far the easiest system out there to use and it's very powerful, so we use it whenever possible.

Some sites are too complicated to make in WordPress unfortunately, community based sites where users are creating the content are easier for us to put together using Drupal as the CMS. Drupal could work in other circumstances as well.
For most sites we do recommend setting up a CMS, some sites that wouldn't need a custom CMS would be: