Do your customers find the tool-tips that pop-up when you hover over your categories annoying. In many browsers, when links use the "title" attribute, the browser will display the infomation in your title attribute as a tool-tip.
So how can you stop this default behaviour. Well, if you just want your categories to be displayed without the tooltip, you can edit your category-tree-branch.tpl file and remove the title text.
Go to: modules/blockcategory/category-tree-branch.tpl and open this file for editing. You will see the following code;
Remove the code highlighted in red above (between the quotes) so that title is left just with the quotes as follows;
title="">
Now you will not see tooltips when you hover.
Note: Check removing titles from categories does not affect your SEO or customer accessibility.