I am not aware that he used any spells in the books. He did use flu powder to transport to the place of the muggle prime minister. In the movies, Fudge used the Sonorus spell to make his voice audible in the entire stadium - but in the books, the games were announced by Bagman, not by Fudge.
Cornelius Fudge, the Minister for Magic, does not die in the Harry Potter series as far as we know. He resigns his post at the beginning of the sixth book, Harry Potter and the Half-Blood Prince, and is really not heard from after that.