Why not use custom post types and don’t add any support for the editor, that is afterall what they are for and the easiest way . The answer in this post covers how to do that,
Hide content box with Custom Post Type?
http://codex.wordpress.org/Function_Reference/register_post_type
To remove that functionality for pages or posts (and custom types) you can try and use remove_post_type_support
. For pages;
add_action('init', 'my_remove_editor_from_post_type');
function my_remove_editor_from_post_type() {
remove_post_type_support( 'page', 'editor' );
}
Ref: http://codex.wordpress.org/Function_Reference/remove_post_type_support
A hacky solution is to use CSS display:none;
for the #editorcontainer
or one of the sub id or classes. You can also then enqueue that style only for particular users.