Confirmation Gateway

I am looking to find a plugin that will help me communicate with the users of my site.

What happens is that the users come to my site to download a file and make an order and they can see other information as well. What I want to do is have a box or something that must be checked by the user acknowledging that they have confirmed everything they have submitted BEFORE being allowed to have access to their upload and download resources.

Is there a way that I can get a check box or pop on my page that will disrupt the page the user is trying to look at and make them confirm information before continuing on to business as usual? Also is there a plugin that can do this and keep record of those actions?

Thanks for the help.