The input format help text is a good way of telling your users about the sort of content that they can enter into any text area. For some users, however, they can get in the way a little and even cause confusion, especially when WYISYG editors are used as much of the help text will be quite useless to most users.
The input format section is controlled by the Filter module, which is built into Drupal core, and it comes with a couple of handy hooks that allow control over this section. The filter tips section is split into two parts, the actual filter tips text itself and the more info link below the tips. If you want to remove these then just pop the following into your theme template.php file and change the function names accordingly.