One thing that's worth mentioning - once you do manage to get data off the disk - *MAKE AN IMAGE BACKUP*

Then if you run recovery tools that screw things up you don't have to resort to the freezer again.

I once ran ddrescue for about 5 days. I'd cool the disk (not freeze, just power off). Run for a few hours, repeat. I aimed big fans into the case whilst it retried sectors again and again - in the end I recovered it completely (well, there were a few hundred Kb of errors but they could have been in unused space).