When it comes to special interests, I either keep it very minimal or not talk about it at all. When it comes to things like antiques, it's minimal. Movies and TV shows from the past are minimal, especially when my discussions talk about VHS tapes...
At school lunch, I'll usually talk about school, sports, weekends, weather, etc etc. just to keep the NTs happy. Most will find me weird if I mention about my large VHS collection of retail + home-recorded tapes full of 1980s nostalgia...
I also don't usually talk about geography. I am a master at geography. I know about every town in WA, and where it's located; as well as many cities and towns throughout the country. I'm sure I'm the only one at my school who knows where Wolf Point, MT is - highway 2 near the North Dakota border, in the middle of farm country/nowhere. But I do NOT mention it, unless an NT needs information about where a city is located.