Basic html question....:)

[superprg]

I have zen cart setup here

http://www.hostmeeting.com/aeol_stoc...16&language=en

I modified the code to show the available sizes only when color is selected. This was done dynamically using javascript

Now I dont get the size value passed to the next page
This is because I changed

FROM

<select name="id[2]" id="attrib-2">
  <option value="4">XS</option>
  <option value="5">S</option>
  <option value="6">M</option>
  <option value="7">L</option>
  <option value="8">XL</option>
</select>

TO

<SELECT NAME="id[2]">
<script type="text/javascript">
regionState.printOptions("id[2]")
</script></SELECT>

So, obviously the value of id[2] is not getting passed.
Is there any simple way to do the same?

Also, the code for 'Add to Cart' image button says

 <div id="cartAdd">
    <div class="qtybox">
Quantity: 
<input type="text" name="cart_quantity" value="1" maxlength="6" size="4" />
</div>
<div class="buybutt">
<input type="hidden" name="products_id" value="16" />
<input type="image" 
src="includes/templates/nones/buttons/english/button_in_cart.gif" 
alt="Add to Cart" title=" Add to Cart " />
</div>          </div>

  <!--eof Add to Cart Box-->

</div>

How to know which page(or action) would be called when clicking that image?