Windows only: Photo gallery application PhotoJoy turns your digital pictures into collages, desktop widgets, or 3D screensavers with just a few clicks. It's the type of application that your mom would like.
Once you've installed the application and selected photo folders to add to the gallery, you can choose from a number of PhotoToys, which are just desktop widgets that show off your photos in various ways, you can activate a collage of photos on your desktop, or you can choose from one of the screensavers to show off your photos while you are away from your PC. You can browse through the web site and find more collages, widgets, and screensavers if the ones that are built in don't appeal to you. PhotoJoy is a free download for Windows only.