hi! my 62 year old mom and i are planning to visit shanghai probably when the climate is starting to be at little colder (with good weather to catch the pleasant scenery), we want to see and eat at Oriental Pearl TV Tower while we also want to visit the great wall. the china visit would take only about 3-4 days. what would be the best time of the year should we travel and what could be the ideal itinerary for this short visit? thanks a lot! =)