In vista you can change the default logon screen background in two ways that I know of;
1. Install LogonStudio and do it through that
2. Use reshack and edit the c:\windows\system32\imageres.dll file manually
Both of these will probably leave you with support issues if the dll is patched at a later date by windows update. Does anyone know of any way to do type of corporate branding to the logon screen that is supported by Microsoft?
I've only been able to find the imageres.dll method. Makes you wonder why MS decided to remove this ability and the ability to set a boot.bmp. Lots of companies want to brand their systems, and with Vista MS just squashed the ability to do it. I don't get it.