IE e Firefox

Olá;

Estou usando uma figura de fundo na página e encima dessa imagem estou pondo outras imagens posicionei usando Float mas quando visualizo no Firefox as posições mudam.

#header {
width: 768px;
height: 143px;
background-image: url('../img/bg_r1_c1.jpg');
background-repeat: no-repeat;
background-attachment: scroll;
background-x-position: left;
background-y-position: top;
}

#content {
width: 768px;
height: 719px;
background-image: url('../img/bg_r2_c1.jpg');
background-repeat: no-repeat;
background-attachment: scroll;
background-x-position: left;
background-y-position: top;
}

<DIV ID="header"></DIV>
<DIV ID="content">

 <DIV style="FLOAT:left; margin-left:20px;">
 <IMG SRC="../../img/logo.jpg" WIDTH="190" HEIGHT="90" BORDER="0" ALT="" >
 </DIV>

 <DIV style="Float:left; margin-left:15px;">
 <IMG SRC="../../img/body-girl.jpg" WIDTH="232" HEIGHT="430" BORDER="0" ALT="" >
 </DIV>

 <DIV style="Float:right; margin-top:10; margin-right:100px;">
 <IMG SRC="../../img/evento.jpg" WIDTH="76" HEIGHT="36" BORDER="0" ALT="" >
 </DIV>

 <DIV style="Float:right; margin-top:100; margin-right:100px;">
 <IMG SRC="../../img/loja.jpg" WIDTH="38" HEIGHT="39" BORDER="0" ALT="" >
 </DIV>
	</DIV>