"When on the tower of Orthanc level, you should already have unlocked all the secret cheats.  Pause the game and hold down all the L and R buttons, and as you hold them down, put in triangle, square, x, circle in that order.  You should hear the sound of two swords hitting.  Then un-pause and continue. You have just put in invincibility and can't get hurt.  It's divided into floors and on one of them Urak-hai archers fire explosive arrows at you. Remember, you can't get hurt.  Run up right beside one and he'll fire an arrow.  Because it's explosive it kills him instantly and you don't get hurt. Repeat that throughout that floor." - callrings

"When you are on the level in Balin's Tomb once you get to the stage when you are using arrow fire stand behind a boulder, but not straightly stay slightly to the left or right and make sure you can hit him with an arrow because he will only hit the boulder, so just keep firing until he breaks down the boulder then move on to the next boulder in the same position this will keep you save from getting hurt by his throwing chain." - Peter

"In the level where you destroy the explosives, use Legolas and as soon as you here him say 'I shall have to find another way' go to the right and there should be stairs. Go up them and there will be a fire. Get your Bow out and shoot one of the barrels. Destroy the rest of the barrels and then just shoot the rest of the orcs. After that go down the stairs and backtrack and go under the watch tower to get some spirit points. Use this with the other characters too." - Schmichael James

"When you are in Helms Deep: Hornburg Courtyardand when the trolls come at the end if you press and hold triangle it will kill them instantly" - Jake

"on the level with the "Isengard Dogs" if you play as Gimli you can win a lot easier ( if you have the cheat "always devastating" on it only takes 3 hits and you get 11,000 experience) unless everything is researched with Gimli this wont work" - Jake