The locks have apparently corroded or gotten gunked up and will probably need replacing once you do get them open. Normally this is a bad thing to do but since the locks need replacing anyway, take a can of WD-40 and, using the little straw that comes with the can, blast a bunch into the key hole. You may have to hold the tip of the straw to force it to open the little spring door that's supposed to keep the elements out. Blast away until the WD-40 runs out, then quickly pull out the straw while the WD-40 is still spraying. Have some rags handy to immediately clean up the overflow. Let it soak for 30 minutes. Gently tap the lock with a hammer every 5 minutes while the WD-40 is soaking (note I said GENTLY tap, not clobber it; the idea is to set up some vibration to encourage the WD-40 to work its way into tiny crevices). After soaking, blast some more WD-40 into the lock then start trying to work the key into the lock. You may have to repeat the blast, soak and tap, blast, and key cycle several times to get it to loosen up.
Once you do get the lock to open, check back with us about getting it off and replaced.