When creating a post using TinyMCE, the output contains the HTML doctype along with other HTML tags that I do not want. I only want the output to contain the content of the post that will be stored in the database and used on other pages of the website. Is there a way to make TinyMCE stop putting these extra HTML tags into the body?
Yes, this is a simple fix. Remove the 'fullpage' plugin from the editor and the problem will go away. This plugins makes TinyMCE a full page editor for building a HTML page. This is why the main HTML page tags are also showing up when you try to build a post.