|If you use a Content Management System like Wordpress, it's just a matter of manipulating the PHP statements or even the settings in the control panel.|
If you had a section on your website like
<div class="adverts">yada yada display the ads</div>
you could set the display attribute to none in the CSS document for that class
and that will hide the display of that section, although it will still be loaded.
I'm thinking you're looking to benefit from a CMS based on reply 3.