When I opened FF this morning the menu bar was gone and I have not been able to find the reset
Right-click a blank spot on the Tab bar, and select Menu Bar.
You get the orange Firefox menu button when the menu bar is hidden.
You can also check for problems caused by a corrupted localstore.rdf file.
And for the sake of completeness: if the entire toolbar area is gone and F10 does nothing, you might be in full screen mode. The F11 function key switches between regular and full screen view.
By the way, what problem do you have that is leading you to want to Reset Firefox? Just in case there is a simpler solution.
If you do use Reset, I recommend you retain the folder on your desktop (Old Firefox Data) for a few weeks in case you discover that something important is missing after your reset.