Since you forgot to tell what recommendations from what sites you followed, it's impossible to comment on what you did. Some are to the point, many others are useless.
If you don't have a recent backup to go back to (why not?), reset your PC per Microsofts instructions in http://windows.microsoft.com/en-us/windows-10/windows-10-recovery-options.
If that fails, it might be a hardware issue; then going back to Windows 7 won't help.
Usually when I go to work in the morning I leave my desktop PC on. When I returned home last night I was greeted with the Windows 10 blue screen of death with the sad emicon. It instructed me to look up the error UNEXPECTED_STORE_EXCEPTION. I rebooted my computer and googled this error and followed recommendations. This morning, I again left my computer running before I left for work, although on this occasion I ran a number of antivirus and antispyware scans. When I returned home tonight I was again greeted with the same Windows 10 blue screen of death. This time it included the error "critical process died". So, as it suggested again, I researched this and it came up with the same recommendations without anyone actually knowing what is causing this or what the errors mean.
I attempted `system restore', however this only gives the previous day restore points when there should be more.
From what i can gather, Windows 10 is deluged with problems and I am considering going back to to Windows 7.
Any help would be gratefully appreciated.
Many thanks in advance.