Visiting beijing with kids and elderly in Nov/Dec

Jui, I think you might go there in late December. You know, some ski resorts use snowmaker machine to create snow when the temperature is ok. So you needn't worry about the weather condition. Even it doesn't snow when you come, you still can ski.

Yes, it's cold if you visit the wall in winter. The temperature is low and it's windy. However, there are still many people go there in winter. As long as you wear winter clothes, I think you can go there too. Do not forget to wear hat, scarf and gloves.