Did Avast cause this problem, how to fix it, are all my files and other stuff gone on my computer?

I installed avast because I heard it was a good anti virus and avg to me is kind of mediocre with virus detection and deletion. I installed avast and everything was going fine until I wanted to scan the whole computer, I had to wait for it to finish scanning the memory and it pointed out that something was corrupted in the memory and I should delete the file and restart computer. After restarting computer an error message came up saying Windows could not start because the following file is missing or corrupt system32\drivers\ntfs.sys. Is my hard drive toast or do I just need new RAM?