Forms plug in recommendation

I’m using WP to power my whole site, not just the blogging part of it. I’d like to allow people to become members of my organization via the site. That requires me to capture a bunch of information…maybe 40 columns, with a mix of fields, checkboxes, and radio buttons.

I’m looking for a robust forms manager that would allow me to save entries to be imported into my Access-based membership DB. Ideally it would permit me to have conditional value lists, conditional field entry (fields shown depend on previous answers), and allow me to save a numerical ID for each value list answer.

Anyone have recommendations for this?

Thanks.