The GR-D23E's DV out connection is Firewire.
So, if I understand correctly, you have the DV camera, the Firewire cable and a
PC with a Firewire port. Windows does not recognize the camera when you plug
it in.
1. Make sure the camera is turned on when it is connected to the PC, which also
should be turned on and Windows loaded. Also, make sure the camera is
in Play mode.
2. Close Movie Maker, then connect the camera. If the firewire port on your PC
is working properly it should recognize the Firewire device by displaying a
dialog box with a list of possible options. One of them should be Video
Capture with Movie Maker.
3. Make sure that the Firewire port is enabled (if such an option appears)
4. Some DV cameras have an option to enable/disable USB/Firewire functionality.
Go into the camera's setup menu(s) and have a look around to determine whether
such an option exists on your camera.
Not much else... I hope the above is useful
Saga