imac g3 will not load from CD drive

After re-opening that giant graphite egg, re-plugging in the cd drive and making sure all of the wires were properly plugged in too, and getting a new kind of hate inside of me for apples quality of construction, I have gotten the disc drive reading again. However it will still not boot off cd.

I just want to upgrade to tiger and it won't let me do so, I can't even find the CD drive in the boot options. but the strange thing is that the os x tiger cd is selectable in the startup disk options, but on boot with the boot menu it does not show up.

is there anything i can do (preferably without spending any money, or very little) or am I stuck with os x 10.3.9 for the rest of my life?

also I'd like to do a clean boot, after all I bought the computer used, and it has a bunch of junk files on it that I'm too lazy to search for and destroy myself.

plus the thing still thinks its named after the school that used to own it, and I'd like it not to.

thanks,
-Tyler

yes, it is the 3 cd set, and I will give an external drive a go in the near future.

my mac was booted off an external drive before, could I burn the images onto an external hard drive and install with those?

thanks so far,
-Tyler

of course, nothing be done with what's in my home.

can the external cd drive be usb?