I may be wrong about this, but I would swear to remembering at some point someone (on this board?) posted their discovery that a cheap broken DVD player they disassembled was actually using an IDE DVD-ROM mechanism attached to a small control/decoder board, and that the "brains" worked to play DVDs when connected to another DVD-ROM drive they had lying around. I'd suggest that *maybe* if you could find such a DVD player and the "Brain Board" was small enough to wedge into the system somewhere you might be able to try some goshawful hack of making the drive switchable between the motherboard and the DVD decoder... but isn't a Mac TV's drive SCSI, not IDE?
(Oooh, so what you do is you hang the DVD player board and a SCSI-IDE bridge off a cable going to the drive, and add a toggle switch that powers either one up depending on what you're planning on doing with the machine; presumably it would be safe to have both IDE controllers present on the cable if only one were powered on at a time? Maybe? I wouldn't swear to it actually.)
Another option would be to sink a *lot* of time, effort, and pain into applying something like the "Takky" mod for Color Classics to your MacTV, stuffing in the fastest PowerMac 5/6500-series board you can find along with compatible video capture device, and either using a G3 card and a software solution or trying to wedge in a DVD decoder PCI card in for the disk playing. But of course this solution would involve irrevocable modifications to your machine's case and wiring. At that point you might as well go all the way and simply gut it, replace the monitor with VGA tube that fits, and place a Mac Mini or likewise inside it along with a USB HD tuner and DVD drive.
(Oooh, so what you do is you hang the DVD player board and a SCSI-IDE bridge off a cable going to the drive, and add a toggle switch that powers either one up depending on what you're planning on doing with the machine; presumably it would be safe to have both IDE controllers present on the cable if only one were powered on at a time? Maybe? I wouldn't swear to it actually.)
Another option would be to sink a *lot* of time, effort, and pain into applying something like the "Takky" mod for Color Classics to your MacTV, stuffing in the fastest PowerMac 5/6500-series board you can find along with compatible video capture device, and either using a G3 card and a software solution or trying to wedge in a DVD decoder PCI card in for the disk playing. But of course this solution would involve irrevocable modifications to your machine's case and wiring. At that point you might as well go all the way and simply gut it, replace the monitor with VGA tube that fits, and place a Mac Mini or likewise inside it along with a USB HD tuner and DVD drive.