Using the Reboot Option

[clydew]

I am using debian-live-503-i386-kde-desktop.img. When I use the Restart 
Computer button, I get the usual shutdown messages until I get the message to 
remove my USB drive and hit enter.  When I do this I get the message to 
continue with Ctrl-D or Press  enter for maintenance.  Ctrl-D just repeats this 
message.  Pressing enter brings me to a shell prompt.  If I do shutdown -r now 
it comes back with the above message.
 
Please advise me on how to do a successful reboot.