This plugin allows you to add the power of Facebook comments to your website. Everyone uses facebook almost daily. You often are logged on and can comment instantly.

Facebook comments are not anonymous, and you will see your friends comments also, thus leading to higher conversions. Using this option also prevents spam from entering comments, facebook does it for you. 

Install the plugin as you would any other extension. Then go to extensions/plugins and activate it. In the settings, you can exclude categories from having a comment function. Below you can see a screenshot as an example.