Welcome to the forums.
You should consider changing your avatar because a lot of women and children visit this site. There are other people do not want to see certain images, each one having a walk of life different from yours.
Macintosh G4? Wow that's with Motorola "PowerPC" processor, isn't it? This is like the other thread with the guy having 128MB RAM, almost. Should be able to use a distro that supports 32-bit in line with Intel "i486" or "i586". For example, not one such as Debian which is supporting the final line of 32-bit processors. By the time those processors came into fashion Apple Corporation completely left out Motorola.
en.wikipedia.org
EDIT: made a clarification according to time.
You would have better luck on the iMac, but still limited largely to 32-bit operating systems and the earliest which were 64-bit only, which might be replete with bugs running it on a Macintosh.