Is google able to spider buttons?

[geebee2]

I'm making a site where interest in a set of products can be registered by ticking checkboxs.

The problem is that if I use hyperlinks for navigation, the form data is lost.

So I am considering of using buttons instead of hyper-links with server-side redirects ( which will always save the form data ) instead.

Another idea is to use buttons instead of a checkbox, in an iframe ( so the whole screen is not refreshed ), and stick with the hyperlinks for navigation.

Anyone tried any of these methods?