Brent,
I know that this is going to sound completely ridiculous, but when I go to the home page, the first feature photo that I click on will expand and work ok. None of the rest will and all give me that 500 error. But I can go back to whichever one I selected first and it will work every time. I have did this four times this morning with different groups of pictures in the featured photos. Don't know if this will give you any thing to go on or not.
Ron