You can do one of two things.
If you just want to get rid of the text that is up there and leave the empty space, you can unpublish the "top" module in your Administrator Console.
If you want to get rid of that space all together and move everything up, you can edit the template HTML in your admin console and remove this:
<!-- top module above header -->
<div id="top-mod">
<div class="shad-r">
<div class="shad-l shad-padding">
<?php mosLoadModules('top', -2); ?>
</div>
</div>
</div>
Personally, I would use the "Comment" HTML tags (<!-- comments here -->)around that so it's commented out instead of completely deleting it.
Let us know if that helps.