Here is the full list of all 80 Borderlands: Game of the Year Edition achievements worth 1,750 gamerscore.
Completed all missions in the Rust Commons
Destroyed Lance Depot
Rescued Athena
Built the New Car: Monster
Killed the Vault Boss
Killed Flynt
Killed the Rakk Hive
Killed Krom
Completed each of the larger challenges in all 3 coliseums
Completed the larger challenge in The Angelic Ruins coliseum
Completed the larger challenge in the Hell-Burbia coliseum
Completed the larger challenge in The Gully coliseum
Completed the lesser challenge in all 3 coliseums
Completed 5 missions in the Rust Commons
Completed all missions in Secret Armory
Killed the Interplanetary Ninja Assassin Claptrap
Killed Commandant Steele-trap
Killed Dr. Ned-trap
Killed General Knoxx-trap
Completed a crazy request for Tannis
Rescued enough Claptraps to earn 42 inventory slots
Completed all missions in the Arid Badlands
Defeated the Rakk Hive, the Vault Boss, Sledge, Krom, or Flynt in a co-op game
Killed Sledge
Completed 15 missions in co-op
Killed 15 enemies with the Soldier's action skill
Earned level 10
Killed 5 Rakk in under 10 seconds
Killed 15 enemies with the Berserker's action skill
Killed 15 enemies with the Hunter's action skill
Killed an enemy plumber-style
Killed an enemy with the Siren's action skill
Killed 25 enemies with shock weapons
Killed 25 enemies with explosive weapons
Killed 25 enemies with incendiary weapons
Killed 25 enemies with corrosive weapons
Completed 5 missions in the Arid Badlands
Discovered Sledge's Safe House
Sold 50 guns to a shop
I bet you never thought you'd be here
Destroyed a Lancer while in a Racer
Paid for a worthless tour of the world's largest bullet
Killed each of the loot midgets
Raced around the Ludicrous Speedway in record time
Emerged victorious from an arena match
Rescued a groupmate from death in a co-op game
Earned level 50
Earned level 40
Earned level 30
Earned level 20
Reached proficiency level 10 with any weapon type
Earned level 5
Reached Level 61
Applied an elemental artifact
Killed Crawmerax the Invincible
Reached Level 51
Played with at least two other players.
Won a duel without taking damage
Won a duel against another player
Discovered Crimson Lance Enclave
Discovered Krom's Canyon
Discovered The Scrapyard
Discovered Headstone Mine
Discovered Skag Gully
Discovered Trash Coast
Equipped a class mod for your character
Discovered Eridian Promontory
Killed 25 enemies by ramming them with any vehicle
Mastered the technology of Pandora
Earned $1,000,000
Killed Ned...sort of
Completed the "Jakobs Fodder" mission
Completed the "Braaaaaaaaaaaaains!" mission
Killed Ned. Again.
Completed the "House of the Ned" mission
Collected 3 panties, 5 fish in a bag, and 15 pizzas
Collected 5 3D glasses
Collected 15 Claptrap bobbleheads
Found 25 oil cans
Found all 6 Claptrap statues