I am not sure if this is the correct way as it post repeatedly but does the work so far.

In my JS:

        //GET SELECTED POSTS/PAGES FOR DELETION	
	$("#delete_selection").click(function(event) {
	 
	  	/* stop form from submitting normally */
	  	event.preventDefault();

  		$.each($('input[name="delete_selection[]"]:checked'), function() {	

			$.ajax({
			  type: "POST",
			  url: 'post_delete_selection',
			  data: 
			  	{ selected: $(this).val() },
			  success: function(data){				

				setTimeout(function () {
					window.location.href = window.location.href;
				}, 1000);

				$('#ajax_message').show().html('Successfully deleted.');
			  },			  
			});				

		});	
	});

My Controller:

        public function post_delete_selection(){
            
        $selectedIds = $_POST['selected']; //THIS GRABS THE VALUES FROM THE AJAX
        $this->posts_model->delete_post_selection($selectedIds);         

    }

My Model:

    	function delete_post_selection($selectedIds) {

	    $this->db->where_in('post_id', $selectedIds)->delete('posts');

		return true;
	}

THE ONLY PROBLEM I HAVE NOW IS THE CONFIRMATION BECAUSE RIGHT NOW IT JUST DELETE THE SELECTED CHECKBOXES. =)