This isn't really too difficult to do on your own.
Here's a screen shot of Excel 2007 which I found using google.com.
I searched for an image using the terms "spreadsheet pie chart excel"
I've uploaded the image below as an attachment.
Click on the image and then press F11 (that's the key that should be above the key on your keyboard with the + and + sign).
Voila! There you go. Just remember to press F11 again to get out of full screen mode. (note that you might have to click on the image or the enlarge IF the image doesn't fill the screen - Firefox shows the magnifying glass while IE shows that odd blue and orange icon (looks like a tiny sail boat on the ocean).
Hope that helps.
Walter