Help… the menu bar in Windows explorer on windows 7 isn’t hiding!! :-\ :-\ its not even checked in layout options! 
Try pressing the Alt key on the keyboard.
Didn’t work…
I found out something omg! It was avast! webrep thing i had to click and it made it hide… omg… uninstalling webrep so i don’t even have it as a addon or toolbar anymore… wtf
Glad you found the problem.