Open notepad and copy the following code in it.
[ExtShellFolderViews]
{BE098140-A513-11D0-A3A4-00C04FD706EC}={BE098140-A513-11D0-A3A4-00C04FD706EC}
[{BE098140-A513-11D0-A3A4-00C04FD706EC}]
IconArea_Image=F:\Celebs\Harsh_Mantri.jpg
iconarea_text= 0x00FFFFFF
{BE098140-A513-11D0-A3A4-00C04FD706EC}={BE098140-A513-11D0-A3A4-00C04FD706EC}
[{BE098140-A513-11D0-A3A4-00C04FD706EC}]
IconArea_Image=F:\Celebs\Harsh_Mantri.jpg
iconarea_text= 0x00FFFFFF
Now save the notepad file in the folder where you need the background picture and the notepad should be saved as desktop.ini Now change the icon of that folder by right click on it and click properties.Then go to customize tab and click change icon.Here change the icon of your wish. Click ok and close. Now you can see the selected picture as background in the folder.