Thread

<form method="post" dynamic_parameters="category|limit" action="{path="members/results"} ">
          <h4>Search by Region:  </h4>
<p>            <select name="category"><br />
{exp:channel:categories channel="members" style="linear" show_empty="no"}<br />
<option value='{category_id}'>{category_name}</option><br />
{/exp:channel:categories}<br />
<option value='???'>View All</option><br />
              </select><br />
<input type="submit" value="Go!" /><br />
            <br />
         <br />
        </form>

<form name="catmenu" action="">
    <select name="selcat">
        <option value="">--Select Category--</option>
        {exp:channel:categories channel="yourchannel" style="linear"}
            <option value="{path='channel'}">{category_name}</option>
        {/exp:channel:categories}
<option value='{path=’template-group/template'}'>View All</option>
    </select>
</form>