darklordoftech said:

What if the officer who says, "Hold your fire." in the beginning of ANH instead said, "Go ahead and fire."?

Good point, probably:

Alderaan wouldn't get destroyed and the Yavin Rebel base wouldn't get discovered. Then some Bothan spies would eventually smuggle out the plans anyway (Because the Empire are rubbish at holding on to their plans). Then the much stronger and more prepared Rebels assault the Death Star with the help of the fully Academy trained and force sensitive Captain Skywalker. The DS by this time has the Emperor and Vader aboard so when it blows they die too resulting in the same outcome as ROTJ.

Difference being that Han is still an ars*hole (If he escaped the clutches of Jabba), Leia and the droids are dead, Luke's family are still alive and still have a regular supply of slave droids, Lando is much richer and more powerful and Ben and Yoda are very, very bored with their lives... also somewhere on Hoth a Wampa still has two arms.