High-end open source blogging applications may have all the features you can think of, but you may not need all that. For simple blogs, a lightweight alternative like Chyrp is worth a closer look. Chyrp runs on the PHP/MySQL stack, has a clean interface sprinkled with AJAX, and administration features that you can learn without resorting to a manual (in fact, there is no manual to speak of).
Chyrp's installation procedure is the first sign of how easy to use and elegant this blogging engine is. The supplied installer script does the heavy lifting for you. All you have to do is download and unzip the package, upload the resulting directory to your Web server, then point your browser to the install.php page (e.g. www.webserver/chyrp/install.php) to begin installation. The installation procedure asks you to provide MySQL database connection details, enter general info about your blog, and configure an administrator account.