Super Mario 64 DS.
The shift to using a stylus or d-pad to move in 8 directions from the full analog movement of the original game made platforming much more difficult than it needed to be. It's why I consider the original N64 version the definitive version of the game.
Even though the graphics were better overall, the dulling of the colors made it lose some of the charm that the original had. Some things just shouldn't be changed.I second this. The DS felt primitive to me when it was new and Mario 64 DS did nothing to help me feel any different. The D-pad wasn't fun to use at all, everything looked jaggy as hell and I really didn't care for the extra content.
Just wasn't fun.