JQuery Modal Dialog

JQuery Modal Dialog

Hello All,

I am using modal confirmation dialog box as shown in the below link

1 ) This works fine for me in Firefox and Chrome browser. However, when I test this on Internet explorer 9. 
The modal dialog come at 'Left Top' position and in other browser By Default it is coming to Center psotion.

I have tries using position atrribute. But still result is same. 

Why this is so ?? 

2) When modal dialog box is opened I am ABLE to click other buttons OR links. How can i disable this ? ho can i set the opacity for the dialog box.
  1. Below is my code..
  2. function myfunction(msg,btn) {

  4. $('head').append('<link rel="stylesheet" href="CSS/jquery-ui.1.10.4.css"/>');

  6. $('<div style="width:auto;height:auto;display:inline-block;">'+ msg +'</div>').dialog({
  7.             resizable: false,
  8.             height: 200,
  9.             modal: true,
  10.             title:  '<%=strConfirmTitle%>',
  11.             position: "center", 
  12.             buttons: 
  13.             {
  14.                 '<%=str%>': function () 
  15.                 {
  16.                     $(this).dialog("close");
  17.                     __doPostBack(btn,'');                  
  18.                 },
  19.             
  20.                 "Cancel": function () 
  21.                 {
  22.                    $(this).dialog("close");
  23.                                
  24.                 }
  25.             }

  27.     });

  29. }