#1SI CAPTCHA Anti-Spam

This is one great plugin what helps you remove spam comments from your blog. You can set up it for your comment form, login form registration form or all of them. And after that if your visitors wants to comment now they need fill one more text box, write phrase from image. I am not to recommend to set up it at begin you create your blog because you don't need this at start and your new visitors too. And ofcourse if you don't have a lot of readers you don't have a lot of spam. Maybe better choice is delete it manual and when you get more visitors and you feel you can't do it manual then it is best time when to set up it. Who ever like to fill one more text box? So its your choice when is best time.

#2 WP-Paginate

Better navigation better for your visitors. And ofcourse looks nice and easy to use. Well i set up it for my blog and you can see how it works. You can replace original with this in comment page, post page and archive page. Its easy to set up. You just need upload it to your plugin directory and after that your theme code where is page navigation replace with this. This code and tutorial you find in installation section of plugin page.

#3 @ Replay

Great plugin for comment section. it allows you or your visitors replay to another comments. See picture bellow how it looks.

#4 WP No External Links

You don't want or you don't like external links from your blog. This plugin deny external links into your web post comments. So for more information click on link.

#5 Greg's Threaded Comment Numbering

If you want number your comments this plugin is for you. This plugin numbers your comments sequentially and hierarchically. With full support for the new comment features available in WordPress 2.7 and later — including threading, paging, and your choice of ascending or descending date order.