Removing Sidebars from Widget.php Admin Page

I’ve done some research and most widget sidebar topics have to do with their display (or not) on the blog page, not the admin page.

I’ve been playing with the Headway Theme, and accidentally reverted my entire Front Page where I’d created my initial widgets. I’ve since recreated the page, adding new widgets back in place.

Long story short, when I go to the Admin/Widget page, I see a long list of sidebar options – half of which are not useful to me in any way. It’s confusing, as some have the same names.

How can I delete the extras? Is it through the Headway theme or is it something I can do through ftp or mySQL? And if the latter, any suggestions of where to start looking?

Thanks for any assistance!