Special Character Appearing in my WordPress Pages Content

My guess is that you pasted something from a Windows environment and that’s the CR (carriage return, I think) character. I’d go into the editor and just remove those line breaks. That should fix the problem. Also, you might look into standardizing the content type meta tag. You’ve got

<meta charset="UTF-8" />

I could be wrong about this, but in XHTML (the DTD of that page), I think you need to use this structure:

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

In your WordPress theme it should look like this:

<meta http-equiv="Content-Type" content="text/html; charset=<?php bloginfo( 'charset' ); ?>">