The metal door is gone already, however the disk is still not recognized by the PC. I get the ol' "This disk is not formatted" routine. Doesn't look too hopeful but hey, I tried.
There are data recovery services out there that will charge you through the nose to retrieve it... but it can be done. Do a search or look in the phone book.
If the physical magnetic disk was damaged, then your pretty much out of luck aside from professional $$$$$ recovery services. How was the disk damaged?
I once had a disk go through the washing machine. I cracked open the disk, took the magnetic part out and let it dry(keeping it covered from dust). Put it back into another dry disk case. Ran Norton disk doctor on it and recovered all the files. Backed the disk up and then shitcaned it.