If you’re looking for a WordPress security plugin, Better WP Security should be at the top of your list. The plugin is a veritable Swiss Army knife for fixing WordPress security issues.
Unfortunately the huge array of settings make the plugin a bit overwhelming for most casual WordPress users. This tutorial walks you through the process of setting up the plugin and activating the most important settings.
If you take nothing else away from this video please take note of one setting that could lock you out of your WordPress site. DO NOT ENABLE any of the SSL options unless you are sure that you have an SSL certificate installed on your server.
For more background on the current state of web security, be sure to watch the WP Apprentice WordPress security briefing.