No, only if you delete your .minecraft folder, minecraft isn't 'installed' so you can't uninstall it either, just deleting it from your desktop does the trick, all your worlds will be left alone.
I think all the free minecraft is gone, and you cannot download it at all anymore.
Copy the minecraft worlds from the file explorer
No it doesn't because it is just like force upating but you do need to update your worlds.
First you must access .minecraft, a hidden folder in My Documents/Application Data. Go into the saves folder to see all the worlds that are on your computer. Now you copy the worlds you want from your computer, put them on the other computer, and paste them into .minecraft's saves folder.
There's only one world that keeps on going and going.
you link it to your minecraft account
Minecraft
yes.
No.
Yes you can, their worlds wont appear on your computer, all you have to do is download the minecraft application. there is no limit on how many users are on one account.
Well there is one way to get into good worlds in Minecraft. Type in a seed.