<style>	
#menu span {
padding: 7px 15px 7px; 
margin-right: 5px;
margin: 10px 0;
width: 100px;
text-decoration: none;
}
#menu .tabactive {
color: #2662DF;
background:#F9F1DD;
}

#submenu {
padding: 5px;
height: 200px;
text-align: left;
font-size: 12px;
width: 720px;
}

.submenutext {
text-align: center;
background:#F9F1DD;
position:absolute;
width:100%;
max-width: 720px;
display: none; 
height: 260px!important;
}
</style>

<script type="text/javascript">
$(document).ready(function() {
$("td.#MenuTxT div.submenutext").hide();
<!--$(".tabs span:first").addClass("active").show(); -->
$("td.#MenuTxT div.submenutext:first").show();
$("div.#menu span").click(function() {
    $("div.#menu span").removeClass("tabactive");
    $(this).addClass("tabactive");
    $("td.#MenuTxT div.submenutext").css({"z-index":"-1;"})
    var activeDiv = $(this).attr("alt");
    $("div."+activeDiv).css({"z-index":"1"})
    $("td.#MenuTxT div.submenutext").hide(1200);
    $("div."+activeDiv).show(2200);
    return false; });
});
</script>

<center><table style="width: 615px;">
 <tbody>
  <tr>
   <td align="center">
    <div id="menu"> <b>
<span alt=#sm1 "style="cursor: pointer;">Кнопка 1</span>
<span alt=#sm2 "style="cursor: pointer;">Кнопка 2</span>
<span alt=#sm3 "style="cursor: pointer;">Кнопка 3</span>
<span alt=#sm4 "style="cursor: pointer;">Кнопка 4</span>
<span alt=#sm5 "style="cursor: pointer;">Кнопка 5</span>
           </b>
    </div>
   </td>
  </tr>
  <tr align="left">
   <td id="MenuTxT"  valign="top"  style="height: 260px;">
    <div id="submenu" width="100%"> 
     <div id="sm1" class="submenutext" style="display:block;">
<br/><br/>
Контент 1-й кнопки
</div>
     <div id="sm2" class="submenutext"><br /><br />

Контент 2-й кнопки
</div>
     <div id="sm3" class="submenutext"><br /><br />
Контент 3-й кнопки
</div>
     <div id="sm4" class="submenutext"><br /><br />
Контент 4-й кнопки
</div>
     <div id="sm5" class="submenutext"><br /><br />
Контент 5-й кнопки
</div>

</div>
   </td>
</tr>
 </tbody>
</table></center>