First things first... Looking at the system requirements, I see mention of how 10.4 removed support for some of the earliest version iBooks and PowerBooks with the old NewWorld ROM, so it might be worth taking a look at this Wikipedia page to try and figure out if you have one of those systems.
http://en.wikipedia.org/wiki/New_World_ROM
Though it does also sound like a possibility is that the optical drive is failing. Check the first part, as it is free and won't really take very long, if that doesn't do it, my money would be on your ODD going bad, and so if that's the case I would probably just scrap the whole plan to upgrade. You'd need to either replace the ODD yourself, and finding parts for a unit that old would be difficult, you could put the HDD in an external enclosure and install the OS onto it via another computer, if you had access to one capable of booting the 10.4 installer, which also seems unlikely given the age of such systems. Otherwise you'd need to buy a firewire external ODD, and that would probably cost more than the laptop itself is worth at this point.
I have a powerbook G3, 700mhz, 80gb HDD, 650mg RAM. Currently I have installed OS X 10.3.9. Originally came with 40gb HDD and MAC OS X 10.1.2, I upgraded the rest.
It has only just recently connected to the internet and installed all required updates from Apple. But have not updated any firmware.
Problem: I have a retail Tiger DVD and Tiger CD installation disks. The Tiger DVD loads and prompts me to restart. However, once rebooted off disk it stalls at the Apple sign and spinning circle. Recently it started giving a SAM Read write error on a black screen soon after.
Tiger CD, wont boot at ALL. I can only view the contents once I boot the computer but it wont boot on start up.
How do I get the DVD or CD for the matter to install. Or should I use another method? Please help, thanks!

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