+3  A: 

Yes, you can use min-height, which is not supported by all browsers (IE6). I would however recommend using a fixed height and setting the overflow to auto. That way your div will have a scroll when the list grows, but it will not affect your design.

<div style="height:200px; overflow: auto;">
    <ul>
        <li>apple</a>
        <li>angry</a>
        <li>antler</a>
        <li>...</a>
    </ul>
</div>
Dustin Laine