Die Harder was the weakest link, primarily because he spent most of his time bickering with the cops. They'd throw in a few bad guys on the ground for him to fend off but the movie didn't work.

I also agree that 16 Blocks could have made for a GREAT Die Hard movie. Switching it so he's fighting against cops and protecting a criminal.

I'd rank 'em:
Die Hard
Live Free or Die Hard
Die Hard with a Vengeance
16 Blocks
Die Harder