I have to sat that Tokyo is really tourist friendly. A lot of things are explained in English and the subway is really easy and good.
Also, most of the people are really friendly and if you show some form of respect or appreciation, they don't mind if you don't speak japanese or know their customs. I was sitting in the green coupet (first class) by mistake on the JR, and the person who checks tickets apologized to me
HAve fun!