Looks like the C: Drive is ILL . I'd replace it with a healthy drive. It looks like its used up all of its free sectors, sectors that drives have to correct for damage, and so further damage will shrink the drive capacity or eventually the drive will completely fail and all data could be lost or further corrupted.
This drive should not be trusted anymore and any important data backed up immediately to avoid data loss. Surprised with the boot count for this drive over 14,000 with 9300 run hours. The computer this drive was in has been turned on and off a lot and average run time less than 1 hour for each boot, or lots of boots because of other problems that kept upping the boot counter.
Do you happen to have any other computers laying around to take a Hard Drive out of and install into this system as a new C: drive?