I'm sorry to tell you that the Summer Palace is best not to eat. There used to be three restaurants in the Summer Palace, namely Li Tingting, Ruyi Pavilion and Zhichun Pavilion, and a government official restaurant on the west side. Now only the Li Ting Pavilion is open in the Summer Palace. However, Zhichunting should have simple Chinese fast food, and the Summer Palace mainly eats portable fast food. Just like supermarkets, there are mostly bread and biscuits, but there are also vendors who secretly sell cooked corn on the east side of the promenade. If you have to eat in the Summer Palace, it's the only way, because the management here is very strict and no open flames are allowed. Listen to the restaurant or special approval. It's best to eat outside the Summer Palace. There are many Chinese restaurants to choose from outside the North Palace Gate. There are only some fast food outside the East Palace in summer, unless you go to Xiyuan, where there are many places to eat. There are many western fast food such as KFC, Pizza Hut, Xiabu Xiabu, McDonald's and Subway. There is an uncle Yang brushing meat under Xiyuan Bridge, and nothing else. Eating in this place is depressing. The newly-built palace gate in the south gate has no place to eat, and the west side is even further away, so there is no food or fast food. World cultural heritage units are particularly well protected. If there is no open fire, how can we eat? If you go to the Summer Palace, you might as well eat more in the morning, have enough fun at noon and go directly to other places to eat in the afternoon. Several decent restaurants on the east side of Xiyuanqiao can eat, but the traffic jams are chaotic (except weekends), and the grade of Beigongmen is almost chaotic.
Besides Tiananmen Square, Wangfujing, Bird's Nest, Water Cube, Great Wall and Summer Palace, you can also go to the Temple of Heaven, Shichahai (not far from Nanluoguxiang in the east), Beihai Park, Wanping Lugou Bridge (War of Resistance against Japanese Aggression Memorial Hall), and visit Dashilan in front of the south side of Tiananmen Square, which is also a good place to take pictures. If the elderly have rich beliefs, it is also good to burn incense in several places in Beijing, such as Yonghe Palace and Baiyun Temple. Beijing Museum is very rich. You may wish to visit the museum. They are all national treasures, including the National Museum and the Beijing Capital Museum. In addition, the night view of Chang 'an Avenue and the flag of Tiananmen Square in the morning and evening are also good scenery.
You can book a ticket online for the concert of the National Grand Theatre or the cross talk performance of Tianqiao Deyun Society to take the elderly to play, which is not bad.
I don't advise you to go to the Great Wall, let alone the weather. When the weather in Beijing is bad in spring, it is windy on cloudy days and the Great Wall is windy and cold, which is not suitable for the elderly. It is best not to attend spring and winter festivals in the suburbs including the Ming Tombs, Xiangshan, Badachu, Jiu Feng, Du Shi and Zhoukoudian. If you want to go, it's not bad to go in summer, and most of these places are young people, especially the Great Wall, and the old people are very tired to climb it.