<html>
<head>
<title>example</title>
</head>
<body>
<div id="dialog" title="Basic dialog">
<form method='post' action='test.php'>
<input type='text' name='renameFile'>
<input type='submit' value='Ok'>
</form>
</div>
<div><input type='button' value='форма'></div>
<script src="http://code.jquery.com/jquery-1.10.2.js"></script>
<script src="http://code.jquery.com/ui/1.11.0/jquery-ui.js"></script>
<link rel="stylesheet" href="http://code.jquery.com/ui/1.11.0/themes/smoothness/jquery-ui.css">
<script>
var dialog = $("#dialog").dialog({autoOpen: false});
$("input[type=button]").click(function ()
{
dialog.dialog( "open" );
});
</script>
</body>
</html>