Tokyo question.....?

Im going to tokyo with my grandmother for a week. We want to stay in ginza, but the cheapest hotel we can find is the ginza capitol hotel. The hotel (luckily) has drop off and pick up services for the tour bus im taking for the week. Do you think I shoul stay in ginza for 140 a night or somewhere like in asakusa for 50 a night and take the subway to every day to the ginza capital hotel?