Hi Rancho079,
Check the below sample and modify as per your requirement.
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/fancybox/2.1.5/jquery.fancybox.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/fancybox/2.1.5/jquery.fancybox.pack.js" type="text/javascript"></script>
<script>
$(document).ready(function () {
$.fancybox.open('#dvLogin');
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div id="dvLogin">
<table>
<tr>
<td>User Id:</td>
<td>
<input type="text" id="txtUserId" />
</td>
</tr>
<tr>
<td>Password:</td>
<td>
<input type="password" id="txtPassword" /></td>
</tr>
<tr>
<td colspan="2" align="center">
<input type="button" value="login" /></td>
</tr>
</table>
</div>
</form>
</body>
</html>
Demo
