Thank you for your help. Although you probably didn't realize it you helped me by putting it inside a $(document).ready function. That took care of it not firing, however it is still pretty buggy.
Basically whenever You hover over one of 5 navigation images it's content slides out below the nav. I tried setting the mouseleave function for a containing div that holds both the nav, and the content for each one.
My problem now is that whenever you leave the containing div, it does not always hide the individual nav content as expected, only some of the time. The faster I move my mouse off, the less likely it is to work. I have a hunch its something to do with the div resizing as the nav content appears, but I'm not 100% sure yet.