function onKeyPress () {
var keycode;
if (window.event) keycode = window.event.keyCode;
else if (e) keycode = e.which;
else return true;
if (keycode == 13) {
alert("The enter key is disabled on this window to prevent accedental submission. Please click one of the buttons at the bottom");
return false
}
return true 
}
document.onkeypress = onKeyPress;