How about this.
Install the 2.4 version of the DVD player onto the PB and see what happens. It can't get worse. Can it?
I have a feeling that the DVDVideoGadgetDriveISDVDDrive file is kind of a question in Pigeon English. Like: "The DVD video Gadget drive thing, is it a DVD drive?"
Normally the answer would be "Yes"
Anyway, 2.4 and if no luck, update the OS, using the PB Software updater Control panel, back up to 9.2.2
Oh, and thanks for the thanks. Appreciated
Since mrmacfixit was good enough to give me his time and wisdom regarding my inability to play DVDs on my PowerBook G3, I took his advice and did a clean reinstall of the system sofware for OS 9.0.4 from the Install disk that came with my computer.
To make sure that nothing interfered with the pristine quality of what was in the new System Folder, I didn't put anything else in it. I put a DVD into the DVD drive (yes, it is one, and yes, it does show up in the Profiler). The DVD disk showed up on the screen, but I got a message saying that AppleDVDPlayer could not be opened, owing to something called "DVDVideoGadgetDriveISDVDDrive" being missing--as indeed it seems to be. I haven't the faintest idea what that is, nor what I can do about it. Any ideas?
By the way, my G4 desktop, running 9.2.2 (as the laptop was doing before I tried running DVDs) and version 2.4 of the DVD software, shows DVDs just fine. Maybe I should just reinstall system updates to 9.2.2 on the PowerBook, transfer over what I need from Previous System Folder and forget about running DVDs on the Powerbook. The only other thing I can think of is to download fresh copies (on the PowerBook) of the system updates, which might make the dear little thing feel comfier. I don't remember which computer I was using when I downloaded the updates I have, but maybe they were on the G4, and my PowerBook doesn't like them.
Not that I'm going to do it anytime soon, if I do it at all. So rest easy, everyone. This is just a report and thanks for your help. You don't have to do anything more--unless, that is, you know something about the mysterious "DVDVideoGadget. . ." file that the PB was asking for and want to tell me about it. No problem if you don't, though.
Thanks again. You've all been very patient, and especially, those (including the aforesaid "P") who tried to solve my problem.