Mac OS 10.4.11 not letting me fully set up

So, about a week ago I bought a 17in G4 iMac with Mac OS 10.4.11 on it. There was an account on the iMac when I got it. So my idea was to factory reset the Mac in single user mode and then after re-setting it up install 10.5 leopard. Although after resetting the Mac in single user mode with the: rm /var/db/.applesetupdone command, now when I boot it up it will play the first time set up video and everything seems like it's working fine until I get to the registration page. everything works good till I get to the registration page where you have to put in your phone number. It won't let me put in the last two digits of my number, it will only let me input 8 digits into the fill in box. And there is no option to skip this page in the set up process.

I've tried to reinstall 10.4 and 10.5 from a USB drive with no success, and I'm really not sure where to go from here. Any help VERY much appreciated.