I prefer the DX version for many reasons. The original was on the Gameboy so the hardware limited it to only black and white. That threw off the mood of the game. Everything else was great though. The DX version could've had better graphics. The Gameboy Color had almost as much power as the SNES, so why didn't they give it A link to the Past type graphics?
So here are the differences between the versions...
1. DX has color
2. DX has 1 new side quest, the photograph one
3. DX has the color dungeon
Another thing in the original that bugged me was the color switches. They were in black and white and you couldn't tell if you raised or lowered certain blocks within the dungeons. I know in Turtle rock i had to go back to the switch so i can get the dungeon item and they were both on opposite sides of the dungeon.