function newWindows(the_URL,ww,wh) 
{
var width = window.screen.availWidth;
var height = window.screen.availHeight;
var left_point = parseInt((width)/2) - parseInt(ww/2);
var top_point = parseInt(height/2) - parseInt(wh/2); 
var the_size = "height=" + wh + ",width=" + ww + ",top=" + top_point + ",left=" + left_point;
window.open(the_URL,"",the_size);
}

//HOW TO USE THE CODE
//      <p>Click here to see the 
//<a href="#" onClick="newWindows('dinner.htm',500,500);" title="This will open the menu in a new window."> menu.</a></p>