The only Philip Seymour Hoffman film I've actually seen in the theatres was Todd Solontz's 1998 film Happiness. He played a guy who makes obscene phone calls to women, would crank one out, and then stick a piece of paper to the goo on the wall. Yeah. So, under-rated comedic skills from that guy, overshadowed of course by his unquestionable dramatic skills.
I found his scenes in Red Dragon to be unintentionally funny. That movie is just....uneven, IMO.