For some odd reason it is saying that the old 17" Intel iMac does not have Mac OSX installed on it so I cannot do the migration from one system to the next.
My sister had trouble with her new Mac finding an older Mac. Unbelievably, this was one occasion where repairing permissions on the old Mac seemed to do something since after doing so, it magically worked. Might be worth a shot.
Once your Mac has finished installing 10.4.11 (I did both Macs from 10.4.10) and restarted successfully, then go to Disk Utility and you should see an option to repair permissions. Don't worry about what it says - just wait til it finishes.
Then go to your new Mac and run Migration Assistant and attach the FW cable at the appropriate point.
We just received 6 new iMacs here at work and this is the first one I am installing and of course I run into this problem (gah). Hopefully the others install without problems.