Form needed for joomla 1.7

Hi need to have created a form which will do the following:

Example, there will be a drop down menu that will have 4 items under it, (about mortgages) which ever one you select will then create some extra questions for the user(s) to answer, all questions will be supplied in word format or different if needed.

This is not a database, once the user(s) have completed the form it will then just email the mortgage company will all the info so that they can call back the customer.

Hope this makes sense, this is a little job i know but the winner will get more job does this sort of stuff as i have a lot more work doing this and don't have the time to complete it.

Thanks