Main Menu Removal

Hello,

I am trying to build a website without the lateral menu on the left (the one with the "Rooms and Services" option), named Main Menu.
The problem is: my articles do not stretch to fit the space, instead, it relocates to the left and leave an
empty space to the right, as seen on the screenshot. I have no modules nor menus assigned to "right" position.

Is there any way to make it center the page without having to edit the template's files?

 

I solved it by inserting an empty Custom HTML module on each position ("left" and "right"), while added an empty " " under the HTML editor.
Still, the images now ocuppies a single collumn...
Edit:
Well, kill me, I found the left/right width configuration under layout on the template manager.
Somehow, it passed unseen the first time I searched...