Here is the full list of all 42 LEGO Star Wars: The Complete Saga achievements worth 1,000 gamerscore.
Complete the game to 100%
Max out the stud counter.
Collect all available Gold Bricks.
Collect all available red bricks.
Collect all mini-kits.
Get 100 points in Arcade Mode
Unlock all characters.
Perform 20 unblockable combo attacks.
Shoot First
Revenge: Destroy The Emperor with Kit Fisto.
Revenge: Destroy The Emperor with Mace Windu.
Crossover: Destroy The Emperor with Darth Maul.
Revenge: Destroy Anakin with Dooku.
Crossover: Destroy Anakin with Vader.
Crossover: Destroy Jango Fett with Boba Fett.
Revenge: Destroy Darth Vader with Obi-Wan.
Wear Every Hat.
Start a Cantina Fight with 50 casualties.
Pull 25 arms off other characters.
Finish Episode VI in story mode.
Perform 200 blaster character dodges.
Set off all three Discos.
Ride all mounts types & ride-ons.
Finish Cloud City still wearing a Helmet.
Finish Episode V in story mode.
Destroy 50 TIE fighters.
Make 100 Build-its throughout the game.
Play through an entire level online
Finish Episode IV in story mode.
Death Star Trench Run without Firing.
Sell your landspeeder to the Jawas.
Destroy 10 characters with one thermal detonator.
Destroy 300 stormtroopers.
Finish Episode III in story mode
Finish Episode II in story mode.
Perform 200 perfect lightsaber deflections.
Finish Episode I in story mode.
Revenge: Destroy Darth Maul with Qui-Gon.
Destroy 5 people with one attack (Jedi super slam).
Disable 5 Droidikas with R2D2.
Destory 300 droids.
Break Jar Jar 20 times.