reset Variable in HTML

[awieds]

I think this is fairly simple but I am stuck on it. I have a page with a menu where the user selects something. based on what he selects I run a query and set a variable. (All this I've done)
Now I have a textbox and I want to set it to that variable. It's set, and onChange the variable changes but how do I reset the texbox to the new value of the variable? Here are the snippets from my code:

sub DescTest(prod)
	dim desRS
	dim strSelect
	Set desrs = Server.CreateObject("ADODB.Recordset")
	strSelect="Select description from productdescription where productid= " & prod
	desrs.Open strSelect, MM_myConn_STRING, 3, 2 ,1
	
	strDescription=desRS("description")
	rs.close()
end sub

<select name="Products" id="products" onChange="DescTest()">
			<%dim j
			for j=lbound(arrproducts) to ubound(arrproducts)-1%>
				<option value=<%=arrproducts(j,1)%>><%=arrproducts(j,0)%></option>
			<%next%>
		</select>


<textarea  name="description" cols="65" rows="9"><%=strdescription%></textarea>

[sde]

i don't know asp well enough to type it off the top of my head, .. but here is some suedo code. mySubmittedValue will have to be set somewhere above the for loop.

<select name="Products" id="products" onChange="DescTest()">
  <%dim j
  for j=lbound(arrproducts) to ubound(arrproducts)-1
    Response.Write "<option value=" & arrproducts(j,1)

    If arrproducts(j,0)= mySubmittedVariable
      Response.Write " selected"
    End If

    Response.Write ">" & arrproducts(j,0) & "</option>"
  next
  %>
</select>

like i said, i don't know asp very well, but this is the logic i might use with PHP. ( with a lot less code )

[awieds]

My code is not even going into the procedure I am calling! Am I calling it wrong?
<select name="Products" id="products" onChange= "DescTest()">