My iMac G3 won't read/boot the Mac OS X disk!

I am having a lot of trouble with an old iMac G3. It has Mac OS 9 on it (I recently updated it to Mac OS 9.1), and I am trying to upgrade it to Mac OS X Panther. I also installed the recent firmware thingy for it. But I am coming across problems...

First I tried loading the Mac OS X disc 1 into the CD-ROM drive, and it detected the CD, but when I tried beginning the installation process, when I clicked the button for it to restart to begin installation, I got an error message reading...

"An error occurred. 'Startup disk was unable to select the install CD as the startup disk. (-2).'"

I also tried rebooting the PC holding the "C" key on the keyboard, but doesn't work, and I also holding the "Option" key down among rebooting, but the OS X disc doesn't show up in the Startup Manager. It DOES show up in the Startup Disk Utility in OS 9 but won't let me select it as the startup disk.

I REALLY need help here. I am tight on money and I don't want to do any hardware upgrades right now. The Mac already has enough memory (578 MB of RAM, to be precise) and has a 7 GB hard drive. I don't really like Mac OS 9 and would much prefer Mac OS X on it.

Please reply with answers/suggestions!