Thanks. Can I do so in PowerPoint? I checked "help," and they talk about how to INSERT an animated GIF. They don't, as far as I can tell, describe how to create one. Thanks.
MS Office used to have a program to animate gifs, but I don't think it is included in 2002. There are a number of simple programs that you can buy - you might look for free ware. Just be careful what you download.
Keynote 3 can do animated transitions. It can export to PowerPoint format if you need to distribute the presentation, but I'm not sure if all special effects are supported.