HTML

<div id="wrapper">
  <div id="content">
    <p>content</p>
  </div>
  <div id="menu">
    <p>menu</p>
  </div>
</div>

CSS

#wrapper {
  width: 200px;
  border: solid 3px #999999; 
}

#content {
  float: left;
  width: 124px;
  height: 100px;
  border: solid 3px;
  color: #FF9999;
}

#menu {
  margin-left: 130px;
  border: solid 3px;
  color: #99CC99;
}