document.getElementById('newzWidget125x125').style.width = "125px";
document.getElementById('newzWidget125x125').style.height = "125px";

var toWrite = '<iframe src ="http://www.newz.ro/widget/125x125.html" marginheight="0" marginwidth="0" scrolling="no" frameborder="0" style="background: #036499; width: 125px; height: 125px"></iframe>';

document.getElementById('newzWidget125x125').innerHTML = toWrite;