Topic: adding a DOCTYPE Declaration shrinked the wev content using tiltviewer

Hi,

I've used this amazing tool to build my web:
www.simplesolutions.co.il
and it works wonderfully!

When runing today the http://validator.w3.org/ on my web i got the worning i'm missing a DOCTYPE Declaration  on my page.
i've entered the declaration code and refresh the page.
The code impact was the shrinking of the page content to 25% of the page height.

I have no previous experience regarding web design, please help me-  what did i do wrong?

my index code is this:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">

<head>

<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />

<title>Simple Solutions</title>

<script type="text/javascript" src="swfobject.js"></script>

<style type="text/css">   
   
    /* hide from ie on mac \*/

    html {

        height : 100%;


    }

   

    #flashcontent {

        height: 100%;

    }

    /* end hide */

   
    #head {
        background-color : #3366ff;
    }
    a {   

        color: #cccccc;

    }

</style>

</head>

<body>

    <div id="flashcontent">TiltViewer requires JavaScript and the latest Flash player. <a href="http://www.macromedia.com/go/getflashplayer/">Get Flash here.</a></div>

    <script type="text/javascript">

   
       
        var fo = new SWFObject("TiltViewer.swf", "viewer", "100%", "100%", "9.0.28", "#000000");
        // TILTVIEWER CONFIGURATION OPTIONS

       
        // For a description of config options, go to:
        // http://www.airtightinteractive.com/proj … tions.html

        //FLICKR GALLERY OPTIONS

        // To use images from Flickr, uncomment this block
       
        //fo.addVariable("useFlickr", "true");

        //fo.addVariable("user_id", "48508968@N00");
        //fo.addVariable("tags", "jump,smile");
        //fo.addVariable("tag_mode", "all");

        //fo.addVariable("showTakenByText", "true");
        // XML GALLERY OPTIONS

        // To use local images defined in an XML document, use this block
        fo.addVariable("useFlickr", "false");

        fo.addVariable("xmlURL", "gallery.xml");

        fo.addVariable("maxJPGSize","650");

        //GENERAL OPTIONS
        fo.addVariable("useReloadButton", "false");

        fo.addVariable("columns", "4");

        fo.addVariable("rows", "3");

        fo.addVariable("showFlipButton", "true");

        fo.addVariable("showLinkButton", "true");
        fo.addVariable("linkLabel", "dvir@simplesolutions.co.il");

        //fo.addVariable("frameColor", "0x99ccff");

        fo.addVariable("linkBkgndColor","0xDDDDDD");
        fo.addVariable("backColor", "0xDDDDDD");

        fo.addVariable("bkgndInnerColor", "0x3366cc");

        fo.addVariable("bkgndOuterColor", "0x000066");   
        //fo.addVariable("langGoFull", "Go Fullscreen");
       
        //fo.addVariable("langExitFull", "Exit Fullscreen");
       
        //fo.addVariable("langAbout", "About");               

        // END TILTVIEWER CONFIGURATION OPTIONS

        fo.addVariable("titleFontSize", "50");
        fo.addParam("allowFullScreen","true");

        fo.write("flashcontent");

    </script>

</body>

</html>