Ultimate Hangman is a fully-featured Hangman game with a bunch of built-in word lists, from Animals to SAT V vocabulary. There are even word lists in other European languages. You can also create your own word list in-game for future use, and you can play with another person at the computer, taking turns entering and guessing the word.
Hangman is really such a simple game, but EnsenaSoft has implemented it so well and for such a low price that it's hard to complain. For those averse to even abstract representations of execution, two of the four themes offer alternative methods of counting down guesses, although the number of guesses cannot be customized. There's a Game Center leaderboard for each language, for those who'd like to spend a day playing Hangman to get their name on an obscure list. And there's a dictionary feature which provides online options to look up a word you weren't able to guess.
Sam's Protip: The shorter the word, the harder to guess. For this reason the most "basic" vocabulary words are actually the most difficult!