This has happened to me several times in the past few months and it always seems to be related to an image file -- either an eps or pdf file that's in the document. Once I replace or remove the image, the PDF exporter works. The problem is that I cannot always replace or remove the offending image. I've contacted Adobe regarding this issue and sent them the files that caused the problem and they found no fault with either image. So why does this keep happening?
I thought it was a font issue, but the one document had no text in it -- just images. I've also tried the same file on my laptop (also running CS6) and the exact same thing happened where it crashed on export to PDF. I do not have any font managment software running on my laptop besides FontBook (whereas on my desktop I'm using Font Agent Pro).
I'm on a mac OS 10.7.5 using CS6 Design & Web edition.