default markup for html editor

Is there a plugin or something that allows me to load some specific markup when i am going to add new page.

For Example when i press Add new page and click on html editor it should already have some markup like

<div id=”left”></div>
<div id=”right”></div>

Also other problem i m facing with html editor is that “enter” to paragraph tag itself. I want it to work like pure html editor like notepad. It should not translate anything on its own. Is it possible??

Thanks