ScrollWall

ScrollWall is a small and freeware Windows application that can automatically change the desktop wallpaper at a user-defined interval.
If you're a tech savvy user, the first thing you may notice about this program is the overall simplicity that obviously appeals to rookies and less experienced users.
ScrollWall however doesn't intend to impress you with a rich feature package, but instead it only offers the very essential options to take care of the desktop background all by itself.
You thus get a single screen that groups all features and a large panel showing the selected pictures. ScrollWall works with BMP, JPG and GIF and supports three different background styles, namely stretch, center and tile.
A preview panel is also available and so are very basic options to adjust the wallpaper changing interval. A dedicated option gives you the power to change the background on every startup.
ScrollWall can be minimized to Tray and this is clearly a good thing, as it runs on low resources and it doesn't affect the overall stability of the system. The Tray icon however doesn't allow further actions, so its only purpose is to provide one-click access to the main window of the app.
On the bad side however, ScrollWall lacks some must-have features, such as support for a broader range of formats and shortcut keys to allow users change the wallpaper on the go.
But to sum up, ScrollWall is a decent wallpaper changing tool for every rookie out there. It requires just very basic computer skills and although a help manual is not available, the user-friendly approach takes care of everything.