How do I customize the Windows Vista Welcome screen?

Secure login screen with CTRL + ALT + DEL before login
Press the Start-button and run this command:
netplwiz.cpl

Note the following command should give the same result:
control userpasswords2

Change to the Advanced-tab and enable Require users to press CTRL+ALT+DEL

This change should match the following DWORD registry setting:
[HKEY_LOCAL_MACHINE \SOFTWARE \Microsoft \Windows NT \CurrentVersion \Winlogon]
DisableCAD = 0

This change should also match the following Local Security Policy -> Local Policies -> Security Options -> "Interactive logon: Do not require CTRL+ALT+DEL".


Note after pressing CTRL + ALT + DEL then the normal Welcome Screen will show with all the pretty user account icons.

Only display the user name and password prompt at login
Open Control Panel and select System and Maintenance
Select Administrative Tools and double-click Local Security Policy
Expand Local Policies to Security Options
Enable Interactive logon: Do not display last user name

This change should match the following DWORD registry setting:
[HKEY_LOCAL_MACHINE \Software \Microsoft \Windows \CurrentVersion \Policies \System]
DontDisplayLastUserName = 1



Now it will only display the input fields for username and password, and it will no longer display all the available accounts with their user names and icons.

Hide a single user account from the Welcome Screen
By adding the username of the account to a special list in the registry, then it will no longer appear on the Welcome Screen. Just create DWORD registry value at the following location:
[HKEY_LOCAL_MACHINE \SOFTWARE \Microsoft \Windows NT \CurrentVersion \Winlogon \SpecialAccounts \UserList]
NameOfTheUser = 0 (1 = Show, 0 = Hide)

Note in Vista the Administrator account is disabled by default and when activated, then it will be displayed on the Welcome Screen automatically. More Info MS KB 926183
Customize the picture shown on the Welcome screen
To change the picture shown on the logon screen for a user:
Open Control Panel and select User Accounts-
Click Change Your Picture and select the picture you want.
Note the available user account pictures are located in the following directory:
C:\ProgramData\Microsoft\User Account Pictures\Default Pictures

Note the default user account picture is located here (Can be replaced with another 128x128 pixel bmp image):
C:\ProgramData\Microsoft\User Account Pictures\user.bmp

Note the picture currently selected by the user is located here:
C:\Users\<username>\AppData\Local\Temp\<username>.tmp.bmp

Disable the Welcome Screen by enabling automatic login
Automatic Login can be enabled with the following steps, so the Welcome Screen is not shown at startup:
Run this this command to open the advanced user management:
netplwiz.cpl

Uncheck "Users must enter a username and password to use this computer" and provide the username and password for the account to use by default.

from:http://smallvoid.com/article/vista-welcome-screen.html