Episode 1:
Start with Anakin already a Jedi and Obi-Wan's apprentice. The Republic isn't against the Trade Federation, but against the Sith Empire. The two go discover the clones. Establish relationship between Padme and Anakin. Have them marry at the end.
Episode 2:
Have Anakin have the vision of Padme's death, by a purple lightsaber. Have Palpatine reveal himself to Anakin near the middle or the end. Have Windu reveal he knows about their marriage and then try and kill Palpatine. Have Anakin kill Windu without hesitation. Feeling relieved, now that the vision has been prevented, Anakin falls to the Dark Side and becomes Darth Vader. At the very end, have Anakin have another vision, only this time Padme dies by Obi-Wan's lightsaber (push the whole "Always in motion is the future"). As the closing shot, show Padme...pregnant.
Episode 3:
Anakin is having more and more visions. Sidious teaches Vader. The Death Star begins construction. Meanwhile, the Jedi Order is being exterminated by Order 66. Anakin himself is killing many Jedi. Padme tells Obi-Wan and Yoda that she is pregnant and involved with Anakin. The three begin a massive search looking for him. Throughout the film, Anakin becomes less and less in love with Padme and more and more in love with power. Sidious gives Anakin orders to meditate on a Sith holocron on Mustafar. Yoda and Sidious fight. Yoda loses. Padme and Kenobi head to Mustafar. Anakin has one final vision of his unborn son defeating him. Outraged at this, Anakin becomes stronger. Kenobi confronts him and the two fight. At the end of the fight, Anakin has won. He injures Kenobi and takes his lightsaber. Padme confronts him and tries to reason with him. Anakin becomes furious at Padme for carrying his child who will defeat him. He reaches for his lightsaber, but Obi-Wan realizes Anakin is about to kill Padme. He force pulls Anakin's lightsaber and charges towards him. Anakin force lightnings Kenobi back and pulls out Obi-Wan's lightsaber and impales Padme. Anakin is in shock that his vision came true. Obi-Wan recovers and force pushes Anakin off the platform and onto the ground. Kebobi quickly strikes again and removes Anakin's human arms and legs, as well as stabs him in the chest (lungs). Anakin falls into the lava and burns up. Obi-Wan recovers his lightsaber and keeps Anakin's. He rushes back to Padme and uses the force to keep her alive until they get to a medic. Same birth scene as ROTS. Padme's funeral, etc. Sidious rebuilds Vader. Vader is outraged at his defeat and hopes Padme is dead. Credits roll.