ah, ok, lets see if I got it right:
open /templates/<yourtemplate>/category_bit.html
and delete this: {if cat_description}
<TR>
<TD width="100%" valign="bottom"> <SPAN class="smalltext">{cat_description}</SPAN><BR /></TD>
</TR>
{endif cat_description}
in your template it might be little different, but the main point is {...} tags and inbetween them.