<form>
<select style="width: 268px" onchange="location = this.options
[this.selectedIndex].value">
<option selected="selected">
Venez venez
</option>


<option value="url1-de-renvoi">
1
</option>

 <option value="url2-de-renvoi">
2
</option>

<option value="url3-de-renvoi">
3
</option>

<option value="url4-de-renvoi">
4
</option>

</select>
</form>