You don't even have to mute the F note on the low E string. Use your thumb to play it, ala Hendrix, SRV, and many blues players:

------1-------
------1-------
------2-------
------3-------
------3-------
------1------- (thumb)

It's not necessarily correct form but it works. Barre chords are probably the biggest hurdle a beginning guitarist has to overcome. Just take your time. You'll get it after awhile. Pick each note individually so that each rings out clearly and isn't accidentally being muted. Don't over-extend yourself to the point of pain. Don't get discouraged.