I just built a DZ77RE-75K system and have the same difficulty with the mouse not working while in the BIOS after a restart from Windows 7 x64. I have to either power off the PSU or Ctrl-Alt-Delete out of the BIOS to get the mouse to work upon re-entering the BIOS. This behaviour is consistent -- like your experience, the mouse cursor is always frozen in the center of the BIOS screen after a restart from Windows. And the mouse works perfectly once booted into Windows.
o BIOS version 0060.
o Mouse is a Logitech G700 wired to one of the motherboard's rear panel USB 2.0 black ports. I am not using the G700's included wireless receiver.
o Keyboard is a Microsoft connected to the PS/2 port. It's interesting that you also have a Microsoft keyboard. Mine is an old Microsoft Office Keyboard.
.....o Because of Microsoft's poor design choice, I have to press the keyboard's F-Lock button before I can press F2 to enter the BIOS. It's unlikely but I wonder if this puts the keyboard into a state which interferes with the mouse. Do you also have to press F-Lock on your Microsoft keyboard?
.....o (I have used a Microsoft Office Keyboard on of all my desktop computers since 2004 and they must be connected to a PS/2 port for full functionality. I have 6 of these keyboards. So if these keyboards are the cause of the mouse difficulties and Intel cannot fix the problem, I'll just live with the Ctrl-Alt-Delete inconvenience.)