Unable to reboot my iMac 2008

I tried to reboot the iMac in Safe Mode by holding down the COMMAND & SHIFT keys simultaneously. I guess that was a mistake. I now have a screen full of programming language that makes no sense to me, with a inactive mouse. I can still type using the keyboard, but the mouse is not responding. It looks like I'm in the root level. Also Power (ON/)FF) switch will not shut down the computer.

Last line of text is: "local host:/ root#"

My System: iMac 2008 with OSX 10.11.7 (El Capitan)

How do I safely reboot my system? (Please see photos attached.)

[Edited by Moderator]