Event.observe(window, 'load', resizeFrame, false);

function resizeFrame() {
    var f = $('myiframe');
    var d = f.contentWindow.document;
    //set the frame height
    f.style.height = d.body.scrollHeight + "px";
    //set the target on the links
    for (var i=0; i<d.links.length;i++){
        d.links[i].target="_top";
    }
}