Q: I do not know how to remove a cannon image browser from my desktop.  It prevents me from shutting down my mac book.

Hello Norma,

Thank you for using Apple Support Communities. 

If you have an app that is preventing you from shutting down your computer, you can force that app to quit. This article provides several ways to force quit an application. 

OS X: How to quit an unresponsive application using Force Quit - Apple Support

A couple of ways from that article:

"Hold down the Control and Option keys on your keyboard, and click the icon of the unresponsive app in the Dock. Select Force Quit from the menu that appears."

or: "Press Command-Option-Esc, then select the unresponsive app from the Force Quit window that appears, and click Force Quit."

Regards,

Jeff D.