change menu home (sounds - videos - photos..)

I would use CSS to adjust the margins and font size.  If you have firebug, Inspect those buttons to find where they are in the CSS files.

The action block html and divs are in templates/base/action_link.html

You could wrap the __action_caption__ in a span tag and control it that way.

Example:

<span class="button_text">  __action_caption__</span>

CSS would be:

.actionsBlock span.button_text{

font-size:12px;
}