I stayed in New Otani for a night. It was an old hotel, but lovely! 5-10 minutes walk from Osakajokoen station and Osaka castle. I booked double room with castle view, though it wasn't excellent angle from my room, but it still a nice view. The room was large and comfortable, a luxury one, with an old style bathroom. And also you will see Lawson near the hotel, between Osakajokoen and Osaka castle.