Thanks guys for the quick responses.
Mathewss: I have noticed that kubuntu in general does a good job at recognizing a physical power button push and shuts the system down nicely in response to 1. Thanks for the suggestion though.
Totallymaxed: I just tried that and it didn't work. I got a screen that said "Shutting Down" with an OK button. and then right back to the "select the orbiter that you want to control" screen. The machine did not shutdown.
Zaerc: I haven't played with the web:admin screens at all yet. But I know that sometimes I will want to simply shut the machine off from orbiter itself. Thanks for the pointer though... when I get a chance I am going to try to control my md with my Palm TX through the web-admin.