@ Chris_Chew - I did a little experimenting with my LVW-5005 which I have been meaning to do anyway. I took the cover off the 5005 Sept 04 US which has a ddw451s drive in it. I hooked it up to my pc with just the IDE cable and power cable to the drive, no power to the 5005 itself. The puter recognized it as a ddw-451s which it is. I right clicked on it in my computer and picked eject and it opened. I was also able to obtain the media code table from it which I posted.
Try hooking it up to your PC and open the tray.
PS - It is playing a Sex and the City DVD right now through Power DVD 5.0