I'd go to the West London Aero Club at White Waltham Airfield. By far it has the best atmosphere of any flying club/school ive ever seen. You can walk there from Maidenhead train station. The clubhouse is friendly, there is great food most of the day, wifi, a great place to meet other like minded people. They host a lot of social functions for members.
Welcome to West London Aero Club - West London Aero Club
Compared to the school 'up the road - no comparison!