I haven't watched Tristan and Isolde before. My library has DVDs of three productions - the 2015 production directed by Katharina Wagner, the production directed by Heiner Muller, and the production conducted by James Levine with Ben Heppner and Jane Eaglen as Isolde. (Pardon my irregular identification of the productions - the library website isn't making it easy to work out when a production's from or who directed it, and my lack of familiarity with opera doesn't help.) Which of these productions do you think would be best as an introduction to Tristan? I hear the Katharina Wagner one cuts the love potion, so I might rule that off first.