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