I am not positive that I have a DVD writer, but for our purposes assume that I do. My problem is that everytime i insert a dvd, the computer (G4 powerbook, 15 inch) just spitz it right back out.
I'm also having this exact same problem - every time I insert a blank dvd-r the damn thing spits it straight back out after the drive trys to read it.
I have a 1Ghz model WITH the superdrive. It used to work fine, but has since started doing this... it could be an issue with Tiger maybe...? OSX is 10.4.1.
Try resetting the PRAM by holding down Command-Option-P-R while you start up. Keep those keys down until it reboots 3 times. See if that helps. Some people report this helping with unrecognized/unusable Apple-supplied Superdrives after upgrading to Tiger.
Reset Open Firmware.
Reboot your computer while holding down Command-Option-O-F. At the prompt, type
reset-nvram and hit the Return key, then type
reset-all and hit the Return key again. Your computer will reboot.