Q: iphoto is stuck on loading print project cannot get it to close or do anything

Can you get it to quit using Force Quit (command - esc)?

What happens if you try opening it in another account?

Quit the application.

You need to look in your user Library/Preferences for the .plist. Hold down the option key while using the Finder “Go To Folder” command. Enter ~/Library/Preferences.  Move the .plist to your desktop.

Open the application and test. If it works okay, delete the plist(s) from the desktop.

If the application is the same, return the .plist(s) to where you got them from, overwriting the newer ones.

If you prefer to make your user library permanently visible, use the Terminal command found below.

http://osxdaily.com/2011/07/04/show-library-directory-in-mac-os-x-lion/

You might want to bookmark the command. I had to use it again after I installed 10.8.2. I have also been informed that if you drag the user library to Finder it will remain visible.

iPhoto 6 and later: Rebuilding the iPhoto library