I don't think a toast-made DVD will be bootable. . . so I'm trying with Disk Utility just now.
see
http://discussions.info.apple.com/we....3@.68ae6139/3
not sure why the link doesn't work at times, but here's the path
go to
http://discussions.info.apple.com/
> Mac OS X > Mac OS X v10.4 Tiger > Installation & Setup > search for "Back Up CD"
btw--I just booted the iMac G4 with a copy I made of the Tiger DVD using Panther's Disk Utility with the G4's Superdrive.
I used Disk Utility's image option to make an image of the volume as a DVD master, then used the master image to burn a copy onto a blank DVD.