$(function($) {
    $(".scroll a, .top-btn").click(function(event) {
        event.preventDefault();
        $('html,body').animate({
            scrollTop: $(this.hash).offset().top
        }, 500);
    });
});​

//usage

<a href="#theContent">Scroll to content</a>


<div id="theContent">
   blah blah blah
</div>

Simply set the id in the content, and use a hash in the anchor to scroll to it.

Smooth Scrolling to Any ID

jquery

jQuery