Are connected to the internet? if yes, you can use this Google screen saver, which is very good. If you are having a internet connection with a limit in download limit it is better you dont try this (or try it with photos in your computer).

• You can use your Picasa Photos in this sceen saver
• You can use Picasa Web albums in this
• You can use photos in your computer and photo sharing sites
• You can use Photo feeds in this. This is a very handy one. You can get a list of Photo feeds from the Google Pack Google Group
• Watch cinematic slideshows with the new Pan & Zoom transition
• Flip through photos with easy on-screen controls

You can read more and download it from pack.google.com