hola amigo gracias por tu ayuda pero hice lo q me sugeristes pero sin sin funcionar, mira el codigo
#header {
background-color: #ffffff;
height:250px;
width:100%;
padding: 0px;
margin: 0px;
float: left;
}
<div id="header">
<img src="logo.jpg" width="286" height="250" border="0"/>
<object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" codebase="http://fpdownload.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=8,0,0,0" width="694" height="225" id="animacion" align="middle">
<param name="allowScriptAccess" value="sameDomain" />
<param name="movie" value="animacion.swf" /><param name="quality" value="high" /><param name="bgcolor" value="#ffffff" /><embed src="animacion.swf" quality="high" bgcolor="#ffffff" width="694" height="225" name="animacion" align="middle" allowScriptAccess="sameDomain" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" />
</object>
<img src="img_der.jpg" width="18" height="200" border="0"/>
<div style="clear: both"></div>
</div>