Is there a Terminal command to eject disk?

There is a Terminal command and it does work under 10.5.1 and 10.5.2. In Terminal type drutil tray eject . You can look at the command man drutil and it lists a lot of related commands. I have sometimes had the mouse method fail to work but so far not the said drutil command. I assume there is only one Disk Recorder involved, otherwiuse you'd have to specify the drive to be ejected.

In researching this I discovered that you can put a permanent eject button on the top menu bar as follows:
go to System->Library->Core Services->Menu Extras
There you will find a veritable treasure-trove of extras, one of which is the eject.menu.
Double-click on the item to install it on the top menu bar.

Extra bonus:
There are many other items in the Menu Extras folder that you can install on the menu bar the same way.
To remove a menu bar item, hold down the Command key and drag the menu item onto the desktop. You will get a "poof" as it disappears. Only the link is "poofed" not the actual item.

In the terminal, enter
drutil list

you should see the drive listed with a number
Then type
drutil tray eject
or
drutil tray eject 1
or whatever the number of the drive was under list

Hold the mouse button down while booting. That should eject the disc.