After publishing a story, does the author retain the rights to characters, settings, ect? What if I were to publish one story, but then I decide that I want to write a sequel or just another story dealing with one of the original characters? Is that something you normally need to worry about?
It does depend on the contract, but I've never seen a publishing contract that takes your copyright. Usually all they ask for is some period of exclusivity, during which you won't resell the work to anyone else. I really don't think it's anything you need to worry about.
That's an interesting question. My guess is that yes, they're included in the copyright, and in order to be bound on that front the contract would have to specifically include them. Contracts sometimes include stuff like the non-exclusive right to include in a future compilation anthology, or non-exclusive audio rights, but I've never encountered anything like movie/game rights, probably because I'm a short story writer rather than a novelist.
i'm assuming that by 'story' you mean a novel and not a 'short story'... the right to adapt your copyrighted work in any way, to any medium, is part and parcel of your copyright... that said, whatever contract you sign with your publisher will spell out who retains or is assigned what rights... which is one of the reasons it's best to have an agent handle those details, since most new writers won't know what's what in re all the legal lingo in a contract... in re characters and settings and all, that's considered aspects of your 'intellectual property' and that, too, is protected by your copyright to some extent... to learn more, you need to study up on all the ins and outs of copyrights at the source: www.copyright.gov