In the vanilla game, the only way to do so is to avoid completing the quest. You can finish the quest without killing him with mods like "The Paarthurnax Dilemma" by Arthmoor on the Skyrim Nexus.
No, Paarthurnax was the only one who could give that option. Killing him forefeits all benefits he and the Greybeards give.
No not any
No, there are not any guns in Skyrim. It is based in medieval times where guns were not invented.
Yey. There are skyrim mods that give you an occupation and workplace.
You can't have any children in Skyrim without the Hearthstone DLC or installing mods.
No, Skyrim is a single player game, but its so massive you won't notice.
as long as you have 2gb of ram, which is how much Bethesda have restricted Skyrim to use on any computer ( without the use of a mod), you should be able to run Skyrim, mediocrely
Yes, you get a map.
It comes out on 11/11/11 and the complete name is TheElder Scrolls V: Skyrim
Any that suits your playstyle.
Steam's listing for Skyrim doesn't include any Mac systems in its System Requirements. So the answer's probably no, at least for now.
If you need a claw to open it, check to palm of the claw in your inventory. If not, look it up on cheatcodecentral.com or any Skyrim forum.