I don't really expect anyone to know the answer since I've never really seen it talked about, but why is it that upon death, the player will forever remain on fire if burned or frozen if iced, and be talked to by people as if still alive? While normal NPCs will not forever remain on fire and they will actually be treated as dead. What makes the player so different? Can it be fixed?

Maybe because when you die nobody wants to put the fire out?

That's why they also say "I'll see you burn!".

What makes us different is that we simply reload an autosave, npc's can't do that...