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