How to insert a drop down box on my page

I have an html page, and I was wondering if it was possible to have something like a dropdown box, like Forum Jump most forum softwares have.


It will go to a different page when you choose an option and click Go.

Please help me.

 

<img src = "go.jpg" onclick = "onClickGo">

<script>
function onClickGo()
{
if (combo.value == 1) window.open("page1.html", target = "_self");
if (combo.value == 2) window.open("page2.html", target = "_self");
}

</script>

 

I don't see a dropdown box

 

Bump..........