PNG is a much better format than GIF, and if you want animation you should probably use Flash or similar. However, animated gifs are still useful sometimes.
In this tutorial we will show how to make a very simple animated gif using Photoshop CS3. If you use CS2 there is some additional information at the bottom of the page.
In this video tutorial will be showing you how to make animated images in Adobe ImageReady, the basics of animation in ImageReady and we make it simple and easy to understand.