Undo Page Delete

I’m not exactly a technological wizard, and I made the mistake of deleting a page instead of re-naming it. Now I have a 404 error on my site, which is annoying and embarrassing. Is there a way to either make that page disappear, or undo the deletion? And if I use one of those handy 404 plugins that redirects, will the error page still show up as a link on my home page as a menu?