Urgent xHTML and CSS help!

Ok, So ive coded the entire layout and its valid. But when I put more content in, the sides of the boxes dont expand, only the content area does. Please tell me what Ive done wrong!

Here is my CSS code:

Code:

---

body {
background-color: #47839d;
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: 10px;
color: #000000;
margin-top: 0px;
}

#wrapper{
width:780px;
margin:0px auto;
margin-top:10px;
padding:0px;
height:100%;
}

#logo{
background:url("images/index_03.gif");
width:780px;
height:115px;
float:left;
}

#navhead{
background:url("images/index_05.gif");
width:175px;
height:37px;
float:left;
}

#conthead{
background:url("images/index_06.gif");
width:605px;
height:37px;
float:left;
}

#nav{
height:100%;
float:left;
width:175px;
}

#content{
height:100%;
float:left;
width:605px;
}

#navleft{
background:url("images/index_07.gif");
width:11px;
height:564px;
float:left;
}

#navbody{
background:url("images/index_08.gif");
width:152px;
height:564px;
float:left;
}

.style1 {
        font-family: Verdana, Arial, Helvetica, sans-serif;
        font-size: 10px;
}

#navright{
background:url("images/index_09.gif");
width:12px;
height:564px;
float:left;
}

#contleft{
background:url("images/index_10.gif");
width:8px;
height:373px;
float:left;
}

#contbody{
background:url("images/index_11.gif");
width:582px;
height:373px;
float:left;
}

#contright{
background:url("images/index_12.gif");
width:15px;
height:373px;
float:left;
}

#contbot{
background:url("images/index_13.gif");
width:605px;
height:18px;
float:left;
}

#usertop{
background:url("images/index_14.gif");
width:201px;
height:32px;
float:left;
}

#radiotop{
background:url("images/index_15.gif");
width:200px;
height:32px;
float:left;
}

#statstop{
background:url("images/index_16.gif");
width:204px;
height:32px;
float:left;
}

#userleft{
background:url("images/index_17.gif");
width:8px;
height:141px;
float:left;
}

#userbody{
background:url("images/index_18.gif");
width:184px;
height:141px;
float:left;
}

#userright{
background:url("images/index_19.gif");
width:17px;
height:141px;
float:left;
}

#radiobody{
background:url("images/index_20.gif");
width:183px;
height:141px;
float:left;
}

#radioright{
background:url("images/index_21.gif");
width:17px;
height:141px;
float:left;
}

#statsbody{
background:url("images/index_22.gif");
width:185px;
height:141px;
float:left;
}

#statsright{
background:url("images/index_23.gif");
width:11px;
height:141px;
float:left;
}

#bottom{
background:url("images/index_24.gif");
width:780px;
height:12px;
float:left;
}

#boxes{
width:auto
float:left;
height:auto;
}

---

And the html code is on:
www.packagehosts.com/sites/habbo/index.html