Problemi con il layout di un form

[tulipan]

OK.
Eccolo:

body{
    background-color:#ccc;
    color:#000;
}
#main{
    width:650px;
    margin:auto;
    text-align:center
}
label{
    border: 1px solid #fff;
    display:inline-block;
    width:47%;
    background: #c0c0c0;
    padding:5px;
}
 input{
     width:47%;
     border: 1px solid #fff;
     padding:5px;
 }


 form{
     padding:5px;
     border:1px solid #fff;
     width: 100%;


 }
 h1{
     text-align:center;
 }


 button, input[type=submit]{
     border: 1px solid #dedede;
     border-radius:5px;
     background:#ddaa11;
     width: 200px;
     height:30px;
     cursor:pointer;
 }
 button[type=reset]{
     background:#fff;
     color:red;
 }


  input[type=radio],
    input[type=checkbox]
  {
    width:auto;
   
 }
 .buttons{
     margin-top:20px;
     padding:5px;
 }
input:disabled{
    color: green
}