The Lunt-Fontanne's mezzanine is the best on Broadway...it is surprisingly close to the stage. I sat in the fifth row over the summer and thought it was excellent. Alternatively, Row Y will be back far.
You don't mention if the family includes children; if so, definitely the mezzanine. Better to look down than have to look around someone's head directly in front of you. The LF orchestra has little to no slope.
Definitely the mezzanine...you will not regret it.