'waiting for root device' can also be caused by the way your drives are setup. I had the same problem a couple of years ago.

To fix i had to first move both the DVD and IDE HDD to the same cable on channel 0 and set the dvd drive as Primary master and hard disk to slave. I think it's something to do with how real macs are setup.

Unfortunately this seems change on different hardware, so it might be worth trying a few combinations.

You could always give another more recent release a go as they will have better driver support. As cgsheen suggested try Leo4All4.1 or LawlessPPC.