First - Welcome to the Forum! I think you'll find it a fun, informative place. The inhabitants tend to be rather strange people, but most of us seem to be relatively harmless.
Decisions like this really boil down to personal taste. The paint applied to the ship in the nineteenth century probably had a considerable sheen - which presumably was affected a great deal by weather and water. It's safe to assume that after the ship had been at sea for a while the paint looked quite a bit different than it did when it was fresh. So there's plenty of room for a variety of approaches.
Modelers agree pretty generally that there's a "scale effect" to gloss - among other characteristics of paint. If you use the same paint on a small-scale model that was used on the real ship (or airplane, or tank, or whatever), it just won't look "right." Many experienced ship modelers simply use flat paints, regardless of the gloss (or lack thereof) on the original. Others think it's appropriate to differentiate between parts of the ship that actually were shiny and parts that weren't. I've seen outstanding models done both ways. One generalization I think is pretty valid: the smaller the scale of the model, the greater the danger that glossy, or relatively glossy, paintwork will look phony.
"Full-size" paint manufacturers (i.e., firms like Glidden and Sherwin-Williams) have quite a list of terms for differentiating between degrees of gloss: "flat," "matte," "satin," "semi-gloss," "eggshell," etc., etc. Just how much difference there is between them varies somewhat between manufacturers. In the hobby paint world, though, I don't think there's any consistent difference between "matte" and "flat," or betwen "satin" and "semi-gloss." (Somebody told me once, quite emphatically, that "matte" is shinier than "flat," but I have the strong impression that British modelers use "matte" to describe what American modelers call "flat.") It's actually easy to get whatever degree of semi-gloss (or satin) black you want: buy a bottle of gloss black and a bottle of flat black, and mix them together till you like the result. (Mix plenty, and keep it in a sealed jar, so you'll be able to touch up things on the model later.) You can also change the degree of gloss after the paint is on, by applying a clear finish of your choice.
For what it's worth, here are some photos of a black-hulled model I built a few years ago: http://www.hmsvictoryscalemodels.be/JohnTilleyPhantom/index.html . It's the New York pilot schooner Phantom, from the resin-hull kit that Model Shipways used to sell. The photos probably don't show the black paint really well, but maybe you can get some impression of the degree of shine on it. I started out by painting the hull with PollyScale flat black ("Steam Power Black," to be specific), with a tiny bit of blue mixed in. (I'm among those who think pure black and pure white don't look right on a small-scale model. I am not among those who think there's a consistent formula for determining the "scale effect" on color.) By the time I was almost done with the model I'd decided that I didn't like the dead flat finish. So (since the paint was really dry by then - don't try this on paint that hasn't had several weeks to dry) I gave it a thin coat of Renaissance wax, applied with a soft cloth and buffed gently. Renaissance wax (http://www.woodcraft.com/family.aspx?familyid=3235) is a British product that's been used by museums for at least thirty years; it isn't cheap, but a jar will last a model builder a lifetime - and it gives a beautiful, soft gloss that, to my eye, looks just about right in applications like this.
Hope that helps a little. Good luck.