Windows has a feature that allows you to create a screensaver from images saved in a folder. You can use pictures you already have or use a PowerPoint slide show.
Open the PowerPoint presentation. If you want to save a specific slide, select it in Normal view.
On the File menu, click Save As.
Select an empty folder or create a new empty folder in which to save your presentation or slide.
In the Save as type box, click Device Independent Bitmap, and then click Save. You can keep the original presentation file name or create a new name.
Click Every Slide or Current Slide Only, and then click OK.
Your presentation or slide is saved to the folder that you selected. After you close your PowerPoint presentation, you will use Windows XP to open the presentation or slide as a screen saver. (Animations that you may have added to the original presentation will not play when you create the screen saver. )
Close your presentation.
Click Start, click Control Panel, and then click Display, or right-click an empty part of the desktop and choose Properties.
On the Screen Saver tab, click My Pictures Slideshow (Photos in Vista).
Under Screen saver, click Settings.
Under How often should pictures change?, set the slider at the interval you want between pictures, or, if you are making a single slide a screen saver, move the slider to Less (three minutes) to avoid a distracting flicker on the screen during the transitions.
Under Use pictures in this folder, browse to the folder in which you saved the presentation or slide.
If you saved a single slide, clear the Use transition effects between pictures and Allow scrolling through pictures with the keyboard check boxes. (screen saver transition effects in this screen saver option are predesigned and do not include the transitions that you set when you created the presentation.)
To preview your new screen saver, on the Screen Saver tab, click Preview