To change the background color of your classic logon window to put in your username and password to logon, follow the next steps:

1. Open the Registry Editor click on the Start button on your taskbar, then click on Run and type "regedit" and click on OK to start the regedit utility.
    
2. Expand HKEY_USERS\.DEFAULT\Control Panel\Colors (see picture 1).
   
   

   Picture 1

3. In the right part of the window you search for the value Background. Double click on it and change the RGB-value. This value you can find in you own graphic software.
    
4. The modifications you made will be in effect after you reboot your PC.