How to Use Text as a Background on Your PowerPoint 2007 Slide
Enter the text in your text box.
Top Secret makes a clever text background.
Select the text in the text box.
To select the text, drag over it.
On the Home tab open the Font Color drop-down list
Choose a light color suitable for the background of slides.
Select the text box.
Click to select the text box.
Click the Home tab.
The Home tab is located on the Ribbon.
Click the Send to Back button.
You may have to click the Arrange button first, depending on the size of your screen.
Clicking this button places the text box behind other text or artwork that you place on the slide.