the top is either at the ski mountain or at the dojo, a place found if you scroll your mouse over you will find.
You can get there from the map or by going to ski village and clicking over by the ski lift. Hope this helps.
You can't
you have to slide on the ice!
If this is 2010 mountain expidition you get there through the gateway in the ski village you go to a survival camp but can only climb the mountain if you are a member.