Sadly, according to the Animal Crossing Wiki:
- All NES games (Except for Clu Clu Land D and Golf) are downloadable via Virtual Console, for Wii by 500 points. This is why unlocking NES games was removed in Animal Crossing: City Folk.
But your question contains a bit of misinformation:
- Some NES games were rereleased in Classic NES Series for GBA. Like Advance Play, the games are slightly streched but two players is available. This is why unlocking NES games was removed in Animal Crossing: Wild World.
The NES games seem to be limited to the GameCube and N64 versions of the game.