For your first question…I’ve narrowed it down to your social plugin. It’s breaking out of the content page which takes other content with it. I looked at the source css for it and I was stunned at the amount of code this thing has…it literally has more css than the Luminescence theme; it has 2007 lines of code (and that is just the css).
As for your other question…I discovered that your social plugin is also causing the button to not function.
So I have a test for you. Disable that plugin and see what happens then and let me know because I can almost guarantee you that you may need to change to a different social sharing plugin, but to confirm my assumption, disable the plugin and see if your page content stays in the container (and that the comment submission button works).