I know this thread is old, but I had a slightly different problem to Centerfold, and hope this reply might be of use to someone.
I'm not tidy; my trash was overlowing, and "Empty Trash" just wouldn't work, whatever I tried. I could delete individual items, but there were SO many it was a nightmare.
I noticed that right at the bottom of my Trash bin was a copy of the Library folder (how did it get there? No idea). I couldn't delete it, move it, nothing. It dawned on me at this point that maybe I couldn't empty trash because the Library folder is deemed essential.
What I was able to do though was highlight the bottom folder in trash, just above the "Library" copy, hold down SHIFT, and click on the top folder in trash. This highlighted everything inbetween, and I was then able to just R-click and delete the lot. I now have an empty trash bin except for the Library folder copy.