wish to visit beijing from 29th oct to 1st nov-2014

According to the weather records, it will be cool bur not too cold at that time, the average temp is about 50 Fahrenheit degree. You can wear the long-sleeved shirts, jackets and pants.
Anyway, the weather changes quickly, so you’d better pay close attention to the weather forecast before you set off.

At that time, the great wall is still open to visitors.