Lombard PowerBook G3 Won't Boot Off 8.6 CD

[Chris Horn]

I installed YDL 3.0.1 on a Lombard PB G3, but want to put Mac OS 8.6 back on 
it.  Unfortunately, I can't get the machine to boot off the system CD.  When 
I either hold down the 'C' key or select 'c' from Yaboot:

1. The CD starts to boot (it's all spun up and reading from it)
2. The screen flickers to the grey stippled screen
3. A cursor appears and you can move it around
4. The cursor freezes and booting effectively halts
5. After a while, the CD stops spinning so fast and idles

What the heck is going on?  It boots to linux just fine, but I don't want 
that!  I can read the Mac CD fine in Mac-on-Linux.  In fact, I just used it 
to install Mac OS in the Mac-on-Linux environment.

Please help, my fiancee is going to kill me!
chris.