ok - for the KB, you must push and hold it for a few seconds. If that dont work then i think that the logitech drivers may be getting in the way.
If you go to your "/System/Library/CoreServices/Menu Extras" folder you will find eject.menu. Double click it. It will now put up in you menu bar, next to your clock a little icon that looks like the eject symbol, only black. Click it. It now gives you the option of ejecting your optical drives.
I am not sure about other removable media such as a ZIP disks. It works on my pmac w/SuperD+ComboD but then i dont have a ZIP drive.
To drag it around the menu bar, Cmd+click it. To drag it off the menu bar, Cmd+click it and then drag it off like you would for something in the dock.
Hope it helps, good luck.