I am actually in the air on my way back from Japan right now.

You will be fine ordering food from restaurants. As others have mentioned, the subway system is confusing for visitors. Even the locals I have been with get confused trying to get on the right train. Taxi drivers speak zero English in my experience and it is tough to tell the, where you want to go.

To answer your other question, English is not widely spoken. Service employees (and just about everyone) are very friendly and accommodating but there is a language barrier.

You will figure it out though! Japan is a great place to visit.