That's the menu for saving/changing/resetting Manual Sorting. (I've updated the thread subject.)
Manual Sorting is off by default, so it must have been turned on. You can turn it off via the View > Sort By menu. It's saved as part of the Folder Format, so you may need to update that, depending on how you have configured things. See Folder Formats: Quick Guide if you're stuck and it keeps turning back on.