Change the Logon Screen Saver:
To change the logon screen saver, follow these steps.
1: Go to START and click RUN.
2: Write regedt32 and click ok.
3: Registry Editor window will open. Find the following registry key:
HKEY_USERS\.DEFAULT\Control Panel\Desktop
4: Double click SCRNSAVE.EXE. Window opens. Change the name according the name of the picture you want to select for the
screen saver. Don't change the extension.
5: click OK.
Its done.
IMPORTANT:
Don't modify other registries if you don't know about it which will cause serious problems if you change them incorrectly.
NOTE:
Make sure that you correctly specify the path to the screen saver. If the screen saver is located in %SystemRoot%\System32,the explicit path is not required.
How to back up and restore the registry in Windows
(http://support.microsoft.com/kb/322756/ )
Change the Logon Screen Saver Timeout Time:
To change the length of time before the logon screen saver starts, follow these steps.
1: Go to START and click RUN.
2: Write regedt32 and click OK.
3: Registry Editor window will open. Find the following registry key:
HKEY_USERS\.DEFAULT\Control Panel\Desktop
4: Double click ScreenSaveTimeOut. window opens. Change the time. Its in seconds.
The length of time that elapses before the logon screen saver starts is changed to the value that you specified.
Enabling Registry Editor:
In some windows error occurs that Registry Editor is disabled by administrator. Enable it by simply running this code.
1.Go to Run and type
"REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f".