Hm. I'm not convinced you meant genres
, Veks. There are tons, many of which are not relevant to what we do here:http://en.wikipedia.org/wiki/Literary_genre
I suspect classifications
might be more useful which are a bit different. Caeli's list is a great start and I don't think we'll use all 30 slots.
Non-Original Setting (this covers anime, movies, books, TV shows, etc)
But then immediately we're into confusion since 'anime' (or anything else based on a TV show) isn't either a genre or a category, merely a basis of the story background. Within anime, for example, you can have Action, Romance, Mystery, Thriller... etc. So I'd suggest we dispense with the idea of anime or TV show based settings as a classification.
Many stories have several classifications. How had you planned to handle that?
Systems will be trickier to handle since I think the fans of each will clamour for the inclusion of their favourites and I expect there's well over 31 systems used on E. I expect people will want to list several just for the various D&D rulesets alone whereas I, as a non-systems gamer, would lump all D&D rules into just one system - D&D.