You've likely heard the recent complaints about Facebook sharing too much information. Turns out fixing your settings can be a little overwhelming with buried options and more than two dozen pages. It's getting pretty tough to get your Facebook privacy right. Fortunately there's ReclaimPrivacy.org.
This site will analyze your current settings, make recommendations, and then point you to the right tab in Facebook to fix it.
This site is highly recommended, free, and easy to use.