My CD drive is not seen by my computer - help

Hello,
I was attempting to install new software.
I installed the CD into the drive. I heard it spin up but it did not autorun the installation program.
I rebooted. No help there.
I tried to run it from the start menu\run but it only sees the "C" drive.
I tried to open it from Windows Explorer ("my computer") but the drive is also not appearing there.
I tried to do a system restore (Windows XP Professional). I selected a system set point about 2 months ago (I don't use this machine often). It went through the motions, shut down, etc. but would not restore ("no changes were made") [this is a different problem that I have encountered in the past but don't have time to address that in detail now - suggestions for this would be appreciated too.]
I looked on-line for a new driver. "Driver Detective" (which seems to operate under dozens of URL's - that's where I landed on virtually every link found after a Google search of "Matshita drivers" or "Matshita UJ-840D") apparently did not find anything wrong with the driver and just indicated that it is a "system driver."
I checked the Device Manager and it tells me that I have a Matshita UJ-840D, that the driver is current and installed properly but the device is not connected.
PLEASE HELP.