Here is the full list of all 8 Dragon's Lair trophies - there are 3 bronze, 3 silver and 2 gold.
Beat the game on any mode.
Never make a correct move in a new game.
Beat the game on hard, arcade mode.
Beat the game on easy, no move guide, 5 lives mode.
Beat the game in 3 lives, any mode.
Beat the game without dying, any mode except infinite lives.
Beat the game on hard, no move guide, 3 lives mode.
Get the highest possible score (427,469).