The results are in! The following is based on information presented by voters last week.
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Vader's Star Destroyer vs. Picard's USS Enterprise
"Launch fighters," Vader ordered.
Captain Piett gave the order and an entire wing of TIE fighers swept out of the Star Destroyer's hangar bay.

Vader watched as the fighters overwhelmed and engulfed the strange ship with the large saucer section. An unusual turbo laser fire Vader had never seen before managed to take out a few of the fighters, but most were making successful attack runs.
"Send in the TIE bomber groups," Vader said as a minor explosion flickered on one of the foreign ship's engines. "Captain Piett, bring the ship in closer and prepare to finish them with a turbo laser bombardment."

The Star Destroyer's engines rumbled and the massive ship moved into position. The enemy ship managed to fire off a few torpedos of some sort, but to no effect. Vader smiled beneath the mask.
They don't know the power of the Empire, he thought.
More explosions appeared on the enemy ship.
"My Lord," Piett said, "it appears they are trying to make the jump to light speed."
"Are we in attack position?"
"Yes, sir."
"Good. Withdraw TIE groups. Fire all turbolaser batteries when ready."
Vader watched as the fighers moved away from their dying prey. A moment later, the Star Destroyer's powerful turbolasers opened up on the helpless ship.

The enemy ship began to come apart.
"My Lord, should we cease fire and take the enemy captive?"
Vader shook his head. "Let them be an example to the rest of the galaxy, Captain."
The turbolasers placed a few more direct hits before the enemy ship exploded and vaporized into a thousands of pieces that twirled across Vader's viewport.
The Dark Lord of the Sith turned toward Piett. "Recall fighters," he said. "We've wasted enough time. Continue on our course to Bespin at your best possible speed."
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Outcome: Star Destroyer wins this matchup easily.
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Gandalf vs. Obi-Wan Kenobi
"Go back into the abyss!" Gandalf yelled as he sent the stranger spinning across the room. The robed man fell hard into the ground with a loud grunt. Suddenly, Gandalf sensed something strange. "Who are you?"
The man stood and ignited a strange colored sword Gandalf had not seen in all his centuries in Middle Earth.
"My name is Obi-Wan Kenobi. I am a Jedi Knight, defender of peace and order in the galaxy."
Gandalf lowered his staff and released a deep, hearty laugh. "Well, well, my friend. I have never heard of a Jedi Knight. However, it seems we are on the same side after all."
Obi-Wan grinned. "I'm sorry we fought. I was about to end you with my lightsaber."
Gandalf laughed. "I'm sorry as well, for I would have erased your entire existence without a second thought."

Both men chuckled and then laughed like any good Scooby-Doo ending.
Outcome: a draw between the two great, but very different, wizards.