From what I know, SFC and DISM are different beasts. Check the web.
I'd suggest that you consider the options out there. If things are as bad as you say, what's the downside from taking a punt? Although, the standard caveat around protecting your data and backing up will always apply.
If you're totally stuck, then it will be a system image restore if you've got a tight back up plan or a clean install if you haven't.