(function(){
	var forms = document.forms || [];
	for(var i = 0; i < forms.length; i++){
		for(var j = 0; j < forms[i].length; j++){
			if(forms[i][j].type != "hidden" && forms[i][j].disabled != true && forms[i][j].style.display != 'none'){
				forms[i][j].focus();
				return;
			}
		}
	}
})();

This code, when placed at the end of the body tag will set focus on the first visible enabled element on the screen.  It considers visibility as well as all forms on-screen

Auto Focus First On-Screen Element

javascript

JavaScript