Are you really using Firefox 11.0? Firefox 11 was released on March 13, 2012 - well over 5 1/2 years old!

As far as viewing the Menu Bar - hit the Alt key to temporarily see it.

To have it appear all the time, hit Alt, then V > T and clicj on Menu Bar so that it has a check-mark. And if that doesn't work for you, look at your extensions. There are a few, like Classic Theme Restorer, that modify features for Toolbars. Consult the download pages for your installed extensions to learn how each works.

Hmm if you do indeed have Firefox 11.0 and Ubuntu then that means you may be using the ancient Ubuntu 12.04 LTS Precise released back on April 26, 2012 and never bothered to update Firefox in package manager since. Yes I realize the old Precise LTS version is supported until April 2017 but it was already using older packages for stability and are even older now compared to current.

Interesting that you have the latest Flash Player 24.0 release though.