To answer the 2nd last question first, the Ubuntu iso disk image is
usually designed to fit onto a cd so you should have no problems there
(assuming the thing works). If you have problems downloading or
burning the iso (disk image) to CD, then you should be able to request
a cd from Canonical (through the Ubuntu website), which they usually
send out free of charge.

As to whether they still officially support the old G3, or just the
new Intel Mac's, I couldn't comment - one for further investigation.

I have a cd from canonical, the computer reads that it is
ubuntu 9.10 but it will not run or install. I am probably doing something wrong.
I might try downloading an older version and try it.

you could try entering "Easy way to install ubuntu on G3 Mac" (or
something like it) into Google ... might be of some help ...

Also, make sure that you have the Mac G3 PowerPC version, and not the
Intel one - they're not binary-compatible ...

I do have the PowerPC version, made sure before I did the original post.

Are you trying to run the cd from within G3? The disk needs to be in the
drive when you start up and should then run automatically. Once it has
run up, you will then have the option to install.

Yes the disk was in the drive, when the computer was started, and no it did not
automatically start ubuntu.

I know nothing about the boot process for a Mac but in a PC you have options
in the BIOS setup. This is (usually) reached by pressing DEL or some other
key when the first screen appears on boot up. These options allow you to
specify which device it boots from, which could be the CD drive, floppy
drive or hard drive. The default is probably not the CD drive. Try to find
this information for the Mac and see how to set it up to boot from the CD.
If you can do that, and you have the Ubuntu CD that works with your CPU etc.
then you should be able to start and install Ubuntu.

You probably are not doing it wrong. Ubuntu will no longer run on PPC. Try
Fedora or Debian.

I will take a look at them................

There is a site called http://www.thebadapples.info/ that is about Linux on
a Mac. The person who runs the site is Klaatu and he is a Mac user. His blog
is at: http://notblog.titradio.info/ He is sometimes called notKlaatu
because ther are many Klaatu's around.

I am not a Mac user, but have known about Klaatu and his podcast for years.
He knows his stuff.

I am not sure what processor your computer uses. If it is powerPC then your
choices for distros is limited. If it is Intel then you can run any distro.

http://fedoraproject.org/en/get-fedora-ppc
http://cruxppc.org/
Links: http://penguinppc.org/
http://www.debian.org/ports/powerpc/
http://www.archlinuxppc.org/
http://www.gentoo.org/proj/en/base/ppc/
http://sourceforge.net/projects/ppclinux/

see also:
distrowatch.com/search.php
It is rather dated. Ubuntu stopped supporting PPC a long time ago. SuSE
recently stopped support and Fedora will stop it after Fedora 13.

Three years ago, Canonical announced they were dropping support for the PowerPC.