Retro Movie Theme Full Page Width

Is there a menu option to use 100% of the screen rather than just the middle section

Hi!
Of course, you can do this. But you will have to edit the code. There is no special option to change the content width as you can see.
Unfortunately, we don't provide any services for editing themes for individual users. But I can point you to the right direction. First of all you will have to inspect the page with the use of Browser console to find the needed container. Then you would better use our blog article on how to change the theme background - actually there you can find how to edit the theme files and more:

https://smthemes.com/blog/browser-devtools-is-at-your-service-or-how-to-change-theme-colors/

To make the content wider you have to find the code:

/*	-==========================- GENERAL -==========================-  */
.container { width: 1000px; margin: 0px auto; }

in the RetroMovie/css/wide.css and delete the code:

width: 1000px;

But this may cause some other problem. So you would better continue inspect the page to solve some issue on your own or hire a developer to edit some code.