ANA will check your bags through, but as you mention you will need to claim them and go through customs. Turn right after exiting, the domestic check in area is a short walk from there.
You will receive first class immigration fast track, and the first class tagged luggage will arrive very quick. Two hours will be far more than plenty of time. My estimation is that you will be at domestic check in not more than 20 minutes after exiting the plane. First class tags actually work in Narita.
The arrival lounge doubles as domestic departure lounge, so hang on to your arrival boarding pass and spend the rest of your time before boarding there. It is right by domestic check in.