By far the simplest way to do this would be to create a text file in Notepad, lets call it Hangman_Words.txt, with one word per line, e.g.
and then read the file directly into a string array using the File.ReadAllLines method.
string words = System.IO.File.ReadAllLines("c:\dir\Hangman_Words.txt");
That's it really.
[EDIT} and you see that OriginalGriff and I are in complete agreement.