Well, for starters, you have to use the ONCHANGE event of the <select> to change *WHAT* is displayed. That is, to show one or the other set of questions/fields.
Have you done that?
You don't even show what those other questions/fields are in your post.
An optimist sees the glass as half full.
A pessimist sees the glass as half empty.
A realist drinks it no matter how much there is.