I have one of the older G5 Mac Pro Quad core machines. When I tried installing my copy of Leopard OSX 10.5, the installer said there was a problem with the 'BaseSystem' and so I tried following the procedure for exiting back to OSX Tiger (my previous OS). Now I'm stuck in what I think is 'Terminal' and I can't get the Leopard disk out. Any suggestions? (I have looked at posts on ejecting CDs/DVDs and will try them when I get home, so thanks for that)