I have been working on computers since my dad bought me a Vic-20 in 1980. I don't think I have ever seen anything easier than simple AJAX with jQuery. Basically all you do is type in some JavaSript like this:
$('#result').load('test.html');
Where #result is the ID of the object (probably div) that you want to assign it to.
Where test.html is the url where the content to be loaded is.
and that is it... seriously.