Here is the full list of all 48 LEGO The Lord of the Rings achievements worth 1,000 gamerscore.
Complete all the Fetch Quests in Middle-earth. (Single Player Only)
Collect all the Mithril Bricks. (Single Player Only)
Craft every Mithril item. (Single Player Only)
Get 100%. (Single Player Only)
Unlock all characters. (Single Player Only)
Collect all the Red Bricks. (Single Player Only)
Collect more than 10,000,000,000 studs. (Single Player Only)
Craft the Fire and Ice Bows. (Single Player Only)
Finish one of Gimli's opponents as Legolas in 'Helm's Deep'.
Defeat 42 Uruk-hai as Legolas.
Reach the top of Amon Hen without being caught once by Boromir. (Single Player Only)
Use the Ent Draught on Pippin.
Fish perfectly 20 times by pressing the icon as it flashes.
Travel to Trollshaws as Bilbo.
Travel to Isengard as every playable Hobbit.
Turn an enemy into a skeleton and make them dance.
Equip Aragorn with the Mushroom Crown.
Achieve True Adventurer in every level. (Single Player Only)
Throw Gimli 30 times.
Dress a character completely in treasure items.
During 'Prologue', jump into the fires of Mount Doom as Isildur.
Complete 2 cooking puzzles.
Complete 'The Mines of Moria' in under 15 minutes.
Complete the Bonus Level.
Defeat Gollum as Gollum.
Unlock all the Map Stones in Middle-earth. (Single Player Only)
Complete 'Mount Doom'.
Complete 'The Black Gate'.
Complete 'The Battle of Pelennor Fields'.
Defeat an Oliphaunt as Legolas.
Complete 'The Paths of the Dead'.
Walk into Mordor.
Complete 'Cirith Ungol'.
Complete 'The Secret Stairs'.
Complete 'Osgiliath'.
Complete 'Helm's Deep'.
Complete 'Warg Attack'.
Complete 'Track Hobbits'.
Complete 'The Dead Marshes'.
Complete 'Taming Gollum'.
Complete 'Amon Hen'.
Complete 'The Mines of Moria'.
Complete 'The Pass of Caradhras'.
Form The Fellowship of the Ring.
Complete a level in co-op.
Complete 'Weathertop'.
Complete 'The Black Rider'.
Complete 'Prologue'.