repeating menu?

hi, in part of my sc i have this code:

#menu{
  float:left;
  width:20%;
     }

and i have this div tag:

<div id="menu">
      <ul>
        <li><a href="about.html">About us</a></li>
        <li><a href="contact.html">Contact us</a></li>
        <li><a href="gallery.html">Gallery</a></li>
        <li><a href="developer.html">Our developer</a></li>
</div>

and when i preview it, it only shows once and stays there statically, how can i have it so that it will scroll down the page with the user, without moving text out of the way?

[JugglerDrummer]

you need to close your <ul> tag for starters :D

oh yeah i saw that after i tried to validate it :D
to be honest i would be happy if it just was plain underneath as long as no text scrolled under, should i not be using float?