What is the HTML to close part of the page?

I already gave you code that will allow you to open and close divs. You can do this basically by setting the css "display" value to "none" or "block".

Now if you want this selection to be remembered for future visits you'll need to have them log in, or you will need to store this in a cookie.

At this point it sounds like the best thing for your level of experience with HTML and JavaScript is a JavaScript library like jQuery, Moo Tools, or YUI.

What you want to accomplish can be done through any of those libraries and if you are going this direction you might want to start playing with them to learn more about dynamic html.

your submit button should have something like that

type="button" onClick="formName.submit();window.close(…

where formName is the name of your form.

Another option is to add in your form onSubmit="window.close();"

See an onSubmit example here:
http://www.w3schools.com/jsref/jsref_ons…