<p>The background should be transparent, but the text should not.</p>

By making an "Enso style" application you mean the Enso launcher?
Here is a screenshot of it:
alt text http://enscreenshots.softonic.com/s2en/68000/68880/3_ensolauncher03.jpg
I would suggest at looking at the open-source C#
Cropper
application.  He does a similar looking GUI with transparent background.  You can open up his project and see how he implements it.
alt text http://img352.imageshack.us/img352/726/cropperuijt3.png