Here's a little script that does the work for you... if there's no Flash, it displays an image only.  It's pulled straight from a page I built, without editing - so you may need to look hard to see what needs changing to make it work for you.  Also need to add the skinpath statements.

      <SCRIPT LANGUAGE=JavaScript1.1>
<!--
var MM_contentVersion = 6;
var plugin = (navigator.mimeTypes && navigator.mimeTypes["application/x-shockwave-flash"]) ? navigator.mimeTypes["application/x-shockwave-flash"].enabledPlugin : 0;
if ( plugin ) {
  var words = navigator.plugins["Shockwave Flash"].description.split(" ");
     for (var i = 0; i < words.length; ++i)
     {
  if (isNaN(parseInt(words[i])))
  continue;
  var MM_PluginVersion = words[i];
     }
 var MM_FlashCanPlay = MM_PluginVersion >= MM_contentVersion;
}
else if (navigator.userAgent && navigator.userAgent.indexOf("MSIE")>=0
   && (navigator.appVersion.indexOf("Win") != -1)) {
 document.write('<SCR' + 'IPT LANGUAGE=VBScript\> \n'); //FS hide this from IE4.5 Mac by splitting the tag
 document.write('on error resume next \n');
 document.write('MM_FlashCanPlay = ( IsObject(CreateObject("ShockwaveFlash.ShockwaveFlash." & MM_contentVersion)))\n');
 document.write('</SCR' + 'IPT\> \n');
}
if ( MM_FlashCanPlay ) {
  document.write('<OBJECT classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"');
 document.write('  codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" ');
 document.write(' ID="script" WIDTH="730" HEIGHT="261" ALIGN="">');
 document.write(' <PARAM NAME=movie VALUE="ara-index-ani.swf"> <PARAM NAME=quality VALUE=high> <PARAM NAME=bgcolor VALUE=#FFFFFF>  ');
 document.write(' <EMBED src="ara-index-ani.swf" quality=high bgcolor=#FFFFFF  ');
 document.write(' swLiveConnect=FALSE WIDTH="730" HEIGHT="261" NAME="ara-index-ani" ALIGN=""');
 document.write(' TYPE="application/x-shockwave-flash" PLUGINSPAGE="http://www.macromedia.com/go/getflashplayer">');
 document.write(' </EMBED>');
 document.write(' </OBJECT>');
} else{
 document.write('<IMG SRC="script.gif" WIDTH="730" HEIGHT="261" usemap="#script" BORDER=0>');
}
//-->
</SCRIPT>
        <!--this replaces flash animation with static image if flash plug-in is not found-->
        <NOSCRIPT>
        <img src="script.gif" width="730" height="261" usemap="#script" border=0>
        </NOSCRIPT>

Hope this helps.