A) No, you will need to download that separately. Get Open Broadcaster. Free and is pretty easy to use. Or if you have a nvidia gpu you can use shadowplay.
B) The only difference is the software.
C) It isn't the software, it's the user. Krita is a free open source drawing application, it has a lot of great features and is also very easy to use.
With that said, the manga edition is only a few dollars extra, and comes with some cool software. You might as well get it. I own the manga, and it is a great tablet.