I have no idea if this will work but go to C:\Windows\System32
and take ownership Take Ownership Shortcut
and give your self permission Permissions - Allow or Deny Users and Groups
and are renaming it to calc.bak.exe
and see if that works. You may need to go to C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories and or C:\Users\YOUR USER NAME\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Accessories to remove the shortcut. If you do not see them use this tutorial to unhide them. Hidden Files and Folders - Show or Hide
Afterwords restart your computer to see if it's disabled I have read there is a possibility that Windows will automatically enable it again. If it does work you will have to find the other .exe and do the same thing.