[eMacMan]

Have you tried creating a new user profile and using the drive from there? If that has failed read-on

Replace the PRAM battery. Could just be that a weak battery is your issue. Should be $10-$20 at any Mac retailer that offers tech service. You can replace it yourself.

IF you still have the back-up you should have run before updating to 10.4.11. I would back-up my current system then revert to 10.4.10. If that fails to resolve the issue then I would indeed be trying to decide if it was worth a new Optical drive or if it was replacement time.

If reverting to an earlier back-up is not possible; Replace the PRAM battery then attempt to boot from the system restore disk. You should be able to open the tray with the eject key, then shut-down with the tray open, insert the disk, close the tray as you boot-up holding down the C key. You don't want to blow away the system, but if you can boot from the factory disks, then it is possible that you have a software issue. In that case, further troubleshooting should be done in the software area, before replacing the drive. Otherwise it is almost certainly the drive.

NOTE: iBooks and MacBooks do not have PRAM batteries.

 

[eMacMan]

...

My eMac's DVD drive has started to add up as well. Does the eMac have a PRAM battery also?

Edit: Well, I just found out they do, but where is the battery located? I didn't see it when I replaced the memory with a larger one recently.

Should be visible when you open the memory access door. May be tucked away but that's where it will be.

Good rule of thumb replace PRAM batteries every 3 years. All the recent Macs have them, except iBooks and MacBooks. They all use the same battery as well, so any good Mac dealer should have them. Quick test is to shutdown your internet connection and reboot the computer. If the Date and Time are screwy it's past time for a battery.

I am not at all sure this is the root of the issue in this case, but I have seen enough times where it was, that it is the place to start.

 

[eMacMan]

OK it is failing to properly burn DVDs. That is an entirely different matter. I would still replace the battery, but I am reasonably sure the issue is with the drive.

Get the latest version of Toast that is compatible with your OS. Toast 5.2x is really out of date.