Change Your Windows 7 Default Logon Screen Without Software

 
Follow this steps to change the Windows 7 logon screen.
1. Download the registry file from here.After Extract the file and double-click on the file to enable this feature.
2. Now, head over to the following folder:
C:\Windows\System32\oobe (“C” is your Windows 7 Installation drive maybe it's possible  "D" or "E" Drives)
3. Here, create a new folder named Info. Again, create a new folder inside the Info folder and rename it as backgrounds.
4. Copy your favorite image file to this folder and rename it as backgroundDefault. Note that the image must be in JPG format and the size should be less than 256 KB.
5. You are done. Reboot your system and see the change.
The following files are supported in C:\Windows\System32\oobe\Info\Backgrounds folder:
* backgroundDefault.jpg
* background768×1280.jpg
* background900×1440.jpg
* background960×1280.jpg
* background1024×1280.jpg
* background1280×1024.jpg
* background1024×768.jpg
* background1280×960.jpg
* background1600×1200.jpg
* background1440×900.jpg
* background1920×1200.jpg
* background1280×768.jpg
* background1360×768.jpg