Is CS6 patched to 8.0.1? Do you get any sort of error message? Does it hang on every file, or just some particular file(s)? Does it work if you restart ID and try to export the file before doing anything else? Can you export the file in the foreground by adding it to a Book (.indb)?
It will do the export to PDF as a foreground task (almost like in InDesign CS4 and below).
I say almost, because it will prompt you for a file name in a different way, suggesting always a name derived from the current InDesign file you want to export from.
Exporting in foreground would be just a suggestion. Nobody knows what's going wrong with creating a PDF out of your InDesign file. Could be that the culprit is a damaged font; or something else is wrong with your InDesign file.