The reason it is 'scrolling' to the top is not because of the return false. It's because in this code:
//On Click Event
$("ul.tabs_ip li").click(function() {
$("ul.tabs_ip li").removeClass("active"); //Remove any "active" class
$(this).addClass("active"); //Add "active" class to selected tab
////////////////RIGHT HERE
$(".tab_content_ip").hide(); //Hide all tab content
var activeTab = $(this).find("a").attr("href"); //Find the href attribute value to identify the active tab + content
$(activeTab).fadeIn(); //Fade in the active ID content
return false;
});
You are making the page significantly shorter by hiding that DIV, thus giving the appearance that you are 'scrolling' to the top of the page. If you were to give that DIV a min-height: 400px; or something like that, you wouldn't get the jogging about. Set the min-height to a reasonable number for your content.
EDIT:
Add this CSS to your .css file:
.tab_content_ip{
min-height: 400px;
}