You can use HTML tags in your image description to specify the font, font size and font color you would like to use in the photo description. For example:
Enter the following HTML code in the photo description dialog.
<font face="Trebuchet MS" size="18" color="#00f080">Flash Slideshow
Maker - Create flash slide show easily</font><br/>
<font face="Trebuchet MS" size="16" color="#0080f0">You can easily
turn a folder full of still images into a stunning Flash slide show
presentation with background music and special transition
effects.</font>
will create a slide show with the effect shown as below: