Microsoft Windows XP usually shows icons for folders like My Music and My Pictures. If a folder contains pictures, Windows XP displays random thumbnails from within the folder. To replace these icons with custom pictures to make browsing your files more fun.
1. In Windows Explorer, right-click the folder you want to add a picture to, and then click Properties.
3. On the Customize tab, click Choose Picture.
4. In the Browse dialog box, click the picture you want to use, and then click Open.
5. Click OK
When you view the folder using Thumbnails view, Windows displays a thumbnail of the picture you selected
Note: Your picture is visible only when you're browsing folders with the Thumbnails View. To access the Thumbnails view, click Thumbnails on the View menu.