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