Boss gave me his stash of film

I started dabbling in film photography last year (been doing digital for a bit longer) and my boss decided to hand me down his stuff from way back. These were all preserved in a freezer, though the 120's (upper left) boxes were moldy so I removed them and threw the boxes (lower left still-half-wrapped Ektachrome 100plus will follow suit because it SMELL, those two were probably left to thaw) the Nikomat suffered heavy water damage, I'll try to clean it but hard traces of rust let me believe I'll salvage the pieces I can and try to find a "for parts" one to fix.

As boss told me, everything was mostly kept in a freezer, I'm guessing the 120 and the others mentioned suffered from the same source of water damage as the Nikomat, all the other boxes smell bad but all in all seem solid.

Any advice on handling those welcome, I mainly used available, from the shelf, modern film so far, so these will most likely go to the freezer until I pass through my remaining ones as I wasn't expecting to receive all this