How to Manage Comments on Your WordPress.com Blog
Open the Comments page by clicking the Comments link on the WordPress Dashboard navigation menu. The Comments page shows all the comments on your blog from the very first day you started. Here you can view the comments, edit them, mark them as spam, or flat-out delete them.
If you set your Comments options so that comments aren’t published until you approve them, you can approve comments in this section as well. To do this, of course, you have to have comments on your blog, and if your blog is new, you may not have any yet.
To manage a comment, find one that you want to edit, delete, unapprove (that is, remove it from your blog page), or mark as spam. If you need to, you can find a specific comment by using the search feature. Just type a keyword in the search box located in the top-right corner of the page and then click the Search Comments button.
When you find the comment you want to manage, hover your mouse pointer over the comment. Six different links appear beneath the comment text as follows:
Approve or Unapprove: If the comment hasn’t been approved, the Approve link appears here. Click Approve to publish the comment to your blog. If the comment is approved, click the Unapprove link to…well, unapprove it. This link puts the comment back into the moderation queue.
Reply: This link drops a text box down on the same page to allow you to reply to the comment right from the Comments page.
Quick Edit: This link accomplishes the same as the Edit link, except that instead of taking you to a new Edit Comment page on your Dashboard, it drops down a Quick Edit text box that allows you to do a fast edit right on the same page.
Edit: Clicking this link takes you to the Edit Comment page, where you can edit the text of the comment if you need to (correcting typos, anyone?).
Spam: This link tells WordPress that this comment is spam and removes it from your blog.
Trash: This link deletes the comment from your blog.