Full list of all 80 Borderlands Game of the Year Enhanced achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Collected 15 Claptrap bobbleheads
Found 25 oil cans
Collected 3 panties, 5 fish in a bag, and 15 pizzas
Completed the larger challenge in The Gully coliseum
Completed each of the larger challenges in all 3 coliseums
Completed the larger challenge in the Hell-Burbia coliseum
Completed the larger challenge in The Angelic Ruins coliseum
Completed the lesser challenge in all 3 coliseums
Reached Level 61
Completed a crazy request for Tannis
Collected 5 3D glasses
Killed the Interplanetary Ninja Assassin Claptrap
Killed Commandant Steele-trap
Killed Dr. Ned-trap
Found all 6 Claptrap statues
Killed General Knoxx-trap
Completed all missions in Secret Armory
Killed Crawmerax the Invincible
Reached Level 51
Earned level 50
Destroyed Lance Depot
Killed each of the loot midgets
Paid for a worthless tour of the world's largest bullet
Destroyed a Lancer while in a Racer
Rescued Athena
Built the New Car: Monster
Completed the "Braaaaaaaaaaaaains!" mission
Killed Ned. Again.
Killed Ned...sort of
Completed the "Jakobs Fodder" mission
Killed 15 enemies with the Berserker's action skill
Killed 15 enemies with the Hunter's action skill
Completed the "House of the Ned" mission
Killed an enemy plumber-style
Completed all missions in the Rust Commons
Completed all missions in the Arid Badlands
Raced around the Ludicrous Speedway in record time
I bet you never thought you'd be here
Killed 15 enemies with the Soldier's action skill
Emerged victorious from an arena match
Defeated the Rakk Hive, the Vault Boss, Sledge, Krom, or Flynt in a co-op game
Won a duel against another player
Won a duel without taking damage
Rescued a groupmate from death in a co-op game
Completed 15 missions in co-op
Play with at least two other players.
Rescued enough Claptraps to earn 42 inventory slots
Earned level 40
Killed the Vault Boss
Reached proficiency level 10 with any weapon type
Discovered Eridian Promontory
Discovered Crimson Lance Enclave
Applied an elemental artifact
Killed Flynt
Earned level 30
Killed the Rakk Hive
Discovered Trash Coast
Earned $1,000,000
Killed Krom
Discovered Krom's Canyon
Sold 50 guns to a shop
Completed 5 missions in the Rust Commons
Killed 25 enemies with corrosive weapons
Discovered The Scrapyard
Mastered the technology of Pandora
Killed 25 enemies by ramming them with any vehicle
Killed 25 enemies with shock weapons
Earned level 20
Equipped a class mod for your character
Killed Sledge
Killed 5 Rakk in under 10 seconds
Discovered Headstone Mine
Discovered Sledge's Safe House
Killed 25 enemies with incendiary weapons
Earned level 10
Killed an enemy with the Siren's action skill
Earned level 5
Discovered Skag Gully
Killed 25 enemies with explosive weapons
Completed 5 missions in the Arid Badlands