You can create a custom keyboard shortcut for shutter for the selection tool.
In Mint Cinnamon 16
-I opened settings, keyboard, keyboard shortcuts, clicked add custom shortcut, name: shutter, command: shutter -s, and clicked update.
-Now, click Custom Shortcuts, click shutter, and under Keyboard bindings, click unassigned, and press the Insert key.
-Now press the Insert key to open the Shutter selection tool.
I haven't figured out what's bound to the Print Screen key yet, but I've learned several other people have the same exact issue with not being able to use Print Screen as the binded key. If anyone else knows how to fix this, let us know.