Pure quality/story wise: The Crying Game. While one of those often criticized retroactively, it's a gritty take on a topic that it was quite ahead of its time on, while combining it with a very interesting topical plot with the IRA stuff. While the treatment of Dill may be considered negative by many, the truth is she was a very strong and well developed character and the relationship, all things considered, was pretty reasonable, particularly for the time. Based on the interaction between Dill and the guy (whose name I can't remember), 20 years later I feel like it would have been a happily ever after for them without the baggage and social issues of the time. Or at least my romanticism always wished that would be the case.
However, "To Wong Foo" holds a special place for me. Objectively it is a completely mediocre movie, and uses the men in dresses trope for pure comedic effect for the most part. But in my life it was one of my first real exposures to anything trans related (because of my age at the time, I didn't see other transgender topic movies until a few years later, since 99% are/were R). Mostly, it was John Leguizamo in the movie that made an impact. Swayze and Snipes, as completely cis male actors, were definitively just men in dresses. Leguizamo however was young, and is naturally on the slim/small side, and looked far more feminine than I'd ever seen a man look. The idea that it was possible for a guy to dress feminine (as they were in drag, not transsexual) and not just be that definitive man in a dress cliche was mind blowing. Any casual experience I had previously (RuPaul, Rocky Horror, random daytime talkshows, etc.) was all stage makeup drag queens or people who still looked entirely masculine no matter what they were wearing (as Swayze and Snipes did). It gave me a hope outside the world of magic or sci-fi(Dr. Jekyll/Ms. Hyde, anime like Ranma 1/2, etc.).
