Coming down to London for a visit in early August. My husband, son and father in law are going to the emirates for a match and myself, daughter and mother in law are going to do some mooching! My father in law is not in the best of health and can't walk far. We would like to spend some time relaxing and eating late morning early lunchtime. Somewhere near kings cross so he doesn't gave to walk far. Cheap/mid price range. Also two teenage children with us. Really stuck as to what to do... Help appreciated!