He says, "We're a couple of swells now." He just won tickets on the Titanic so he jokes that they're part of the elite class now. Swells is an old-fashioned term that referred to the rich, fashionable class of people. Rose and her family were swells. It's no longer used in modern English.

New Oxford American Dictionary swell | swɛl | noun 5 informal, dated a person of wealth or high social position, typically one perceived as fashionable or stylish: a crowd of city swells.