Form Generator

[eluser]Seller[/eluser]
Hello. Apologize for my bad English. I am developing a site on the similarity http://www.alibaba.com/. On this website when placing a new ad., depending on the selected subcategory dynamically generated form with the characteristics of the selected categories. For example, if a person has chosen a category Computer Hardware & Software and subcategory Laptops, then for this subcategory is generated form with features for Laptops. Just these characteristics are associated with the search product, such as a person has entered into a search form Laptops, then on the search page appears characteristic of this section as filters to refine your search.
I made 4 of the table to store the fields. First table fields (id, title, type) the second fields_values (field_id, good_id, value) third fields_groups (id, title) and the fourth table in which we write what fields belong to which group fields_in_group (group_id, field_id ) and to each category of the directory I can attach some group of fields. But I have a problem now. How can I store the values for option and bind them to a select field? I have thought that if we make another table to store values and the option to link this table on the ID of the table fields. Please, tell me! Am I in right direction think?