Even better, take out "version"; makes it clunky.
Pokemon Red and Blue
Pokemon Gold and Silver
Pokemon Ruby and Sapphire
Pokemon FireRed and LeafGreen
Pokemon Diamond and Pearl
Pokemon HeartGold and SoulSilver
Pokemon Black and White
Pokemon Black 2 and White 2
And PLEASE have them separated from third versions. The only pieces that should be under Emerald, Crystal, Yellow, Platinum, etc., are those that FIRST appeared in those games.
I hate that they're put together, as an example, "Diamond, Pearl, and Platinum" when the majority of the pieces are from Diamond and Pearl. Platinum is NOT the same game.