A JavaScript object can be of great help when you need to pass multiple values to a Modal Window. E.G.

 var objArgs = new Object();
 objArgs.Value1 = "Value 1";
 objArgs.Value2 = 2;
 var modalWindowFeatures = 'dialogHeight:600px;dialogWidth:600px;scroll:no;status:no;resizable:no';
  url = 'relative/path/to/page';
  var returnValue;

  returnValue = window.showModalDialog(url,objArgs,modalWindowFeatures );

If you have a gridview/repeater control or other tabular data within a div, scroll bar appears when height of data gets bigger than that of DIV. If you want to scroll down to a certain position, you can use 'Element.scrollTop' property in Javascript: document.getElementById(div... = PixelsToScroll; Calculating the PixelsToScroll may vary depending on scenerio, In my case, I wanted to scroll down to a selected row within Repeater control. Row was selected using RadioButton and page ......