Make Windows 7 Login Screen look like the Windows XP login screen

According to this thread, it's not possible because both Windows Vista and 7 does not use the old MSGina.DLL file that provided the said dialog box. However, there's a suggested registry edit in the same thread that would allow you to hide accounts you do not wish to display at the logon screen.

EDIT: Apparently I didn't do a complete search. There's an opensource project called pGina which might help here. It requires .NET Framework v3.5 SP1, and it has an LDAP authorization-related plugin. However, support for Windows 7 is still pretty much a work in progress.

EDIT 2: Another possible solution in the works: someone is porting their custom GINA to a Credential provider suitable for use in Vista (and possibly Windows 7).

http://www.mydigitallife.info/2010/01/28/revert-and-change-to-xp-classic-logon-screen-on-windows-7-or-vista/

I'm the guy behind Paralint.com, pointed out by lsxek. I'm working on the back end, and my work will not help you bring back the XP look, sorry.

Getting credentials from a user is handled by a Credential Provider. There are samples in the lastest Platform SDK. If you choose to go down that path, you will end up doing this:

1. Build a Credential Provider that informs LogonUI.exe of the field you need
2. Fill those fields with data, like a list of domains
3. When notified that you tile was filled out, serialize the credentials for LSASS.exe to handle

If it is just a matter of rearranging the look of the logon screen, Microsoft's samples will give you a good head start. But I would - and I'm sure you have by now - consider the benefits you will get out of that work, considering maintenance and all...