My hard drive has been on the brink of death for months now, but it's still finding a way to go strong, although it clicks a ton everytime I boot it up. Is the hard drive still working to some capacity? You may have time to get the files to a USB, transfer them to a SSD or upload it into the cloud for the time being. If not, you may have to resort to waiting a while then trying to use the hard drive and hope that your going to be one of the lucky ones.
The ONLY solution (And this is kinda drastic)
Is to backup all the files and put them on a new hard-drive
But if theres a virus on your hard drive, say goodbye to your memories!
A virus simply on the hard drive normally won't do anything to the files themselves. Most viruses around today steal data rather then destory it. Also, backing up absolutely everything is a waste of time, just back up the stuff you care about, and let stuff like the whole windows folder rot.