need help with install from dmg file.

[jdc]

Ok, not sure what Im doing wrong.

I have an iLamp, G4 800, running a fresh install of 10.3.9.

I have a dmg of 10.4.6, expanded and I have burned to a DVD using the finder and using Toast, but neither will boot the iMac.

I have tried the DVDs in both the internal DVD and with an external firewire DVD player.

Is there some way Im supposed to burn the DVD to make it bootable?

I dont see any way to use the dmg to boot the iMac, since the dmg disappears if you try to boot from the image.

any tips welcomed.