Robert,

Will your sticky up top still work if my OS boot disk is 10.4.10 and my OS on the system drive is 10.5.8?

It should work perfectly; the boot disk is just serving as a method to boot away from your internal drive and get access to Disk Utility. The functionality is the same from v4 to v6 OS.

Thanks Robert thought it was better to ask first. I have a spare external HD that will now use to keep a clone all the time of my system drive.