Not a mod, but just chiming in: My personal approach to this (though I'd dealt with it mostly in crossover fic) is to pretend my character comes from an Earth which didn't have whatever fiction the other characters are in, just because otherwise it gets weird. But it's up to the mods of course; I'm very curious.
Frank wouldn't have read Death Note anyway, for timing and personality reasons, and Transformers the movie came out after he left too. But maybe he could have seen Scrubs. I think he'd be very weirded out if someone told him he was a video game character though, and if they played the second game that his son was in and told him about that he'd go crazy. But that's more due to the nature of that game.
But again, I'm just rambling, not answering the question. ^^