Re: G4 won't boot in OS 9
Ahhhh yes. Old school. If you're actually trying to boot in OS9 you may want to hold the shift key right after the chime, hold it until it says "extensions disabled", to start with extensions off. If you're launching classic from within OSX open the "Classic" system preference and then go to the advanced tab and turn off extension from there. That'll usually get you on enough to see what's up, run the extensions manager and trial and error your way out of it. Barring that it might be a good idea to go into the OS9 system folder and gut everything out of the Font folder that isn't the name of a city. Many a healthy OS9 was disabled by nothing more than an ugly font.
When you say "new" G4 it's either "new to you" or you typo'd G"5". Either way. Instructions hold.