01. Connect the iBook to your Mac Mini, via a FireWire cable.
02. Turn ON the iBook with the 'T' key pressed, until it boots into '
target' mode.
03. Turn ON the Mac Mini.
When the Mac Mini's 'Desktop' appears, the boot drive's icon - of the iBook, should displayed on the Mac Mini's 'Desktop'.
04. Insert the 'retail' copy 'Tiger' installation DVD, into the Mac Mini.
05. Run the DVD's installer - which will reboot the Mac Mini.
06. Attempt to install 'Tiger' onto the iBook.
You can disconnect the FireWire cable during the reboot - if you successfully installed 'Tiger'; or anytime afterwards (if the installation failed) - by dragging the Mac Mini's 'Desktop' icon of the iBook onto the 'Dock' based trash can.
If the installation process freezes, when attempting the above - this may be an indication of a non-clean DVD surface, defective DVD, etc. If the latter, you should be able to obtain a free replacement from Apple Computer Inc.
Either way, post your result(s).