Han Solo.
Advanced interstellar civilization, cool spaceship, married to a Hot Princess. Pals with a Wookie & a Jedi Master.
Nifty.
interesting you wouldn’t have picked episode 2 anakin who had a cool spaceship, married to a hot princess, pals with a gungan, and WAS a jedi master.
Anakin was never a Jedi master. He was, at best, a knight.
That said,he had the hotter princess, as his was played by Earth’s hottest woman.
On the other hand, leaping into Anakin means living with the memories of being the galaxy’s biggest wanker for a week. I’m not sure even sex with Natalie Portman is worth that, particularly as one could just as simply leap into the Toby Mcguire character from BROTHERS during the week before he shipped out to Afghanistan.
Who the F*CK wants to pal around with Jar-Jar?:mad:;)
Simon Tam from Firefly. Granted, you’re a clueless dork, but you get to follow along with Mal & Co., and the hottest mechanic in the known universe lusts for you. Believe me, if I was in Simon’s shoes, Kaylie wouldn’t be just dreaming about me…
True. Dat.
Why bother with Superman, his powers pale to the most powerful fictional character of all - <<<GOD!!!>>>
And if I was <<<GOD!!!>>> then my all encompassing power would surely allow me to stay on longer than a week.
Please welcome your new omnipresent overlord…
I haven’t tried it out myself, but I seriously doubt the QLA is going to work on God, and I also suspect that even trying at best amuse him and at worst seriously piss him off. Anyone wishing to prove me wrong is invited to steal and/or invent his/her/its own leaping chamber.
John Horatio Malkovich
I’ll take Lawrence Newton from Fallen Dragon, but specifically after he gets his own ship from the aliens, goes through the wormhole, then reunites with his love in the past on Amethi.
Meeting giant space aliens, getting new patternform body construction, flying a custom spaceship through a wormhole into the past, then sleeping with an energetic young hottie as a wealthy young guy on an alien planet until my week runs out.
Just before it does, it’s back to the wormhole to do it again and again until I get bored.
Later answers will likely include any of these, if I know my fellow Dopers. 
Jerry Seinfeld the character
The hell they will. Only a madman would want to live through any of the interesting part of any of Tolkien’s work.
We can specify the point in the fictional timeline, right? If so, then Ultimate Reed Richards, from well before Ultimatum.
Young, brilliant, a very exciting life, a very cool power (even better than the original), and one hot (and smart) girlfriend.
Plus, I think, given a week and the idea, I/Reed could reverse engineer the Quantum Leap Accelerator…
Pick a Mary Sue, any Mary Sue. I’d be beautiful and perfect and wonderful and do everything right. And everyone would think I’m awesome.
ETA: Not that I’m not already perfect and wonderful and the [del]secret[/del] master of the universe, you understand.
Since trapping Ultimate Reed Richards for a week in my quantum leap accelerator is logically equivalent to giving him the quantum leap accelerator for his own use, with the added bonus of having a pissed-off Sue Storm and Ben Grimm track me down and beat the crap out of me, I will have to suggest that you steal his life your ownself.
Tony Stark, early Michelinie era.
You didn’t specify science fiction, did you? ::Checks spoilered rules to verify:: Whew! O.K. then:
Harriet Vane, for the week of Busman’s Honeymoon.
Being me, I’ll just stretch Skald’s rules a little bit, and leap into the fictional character of pro wrestler “Cowboy Bill Watts” (coincidentally played by a real person also known as Cowboy Bill Watts), during his run against Hotstuff Eddie Gilbert and the Russians. IIRC, Watts was allegedly sleeping with Dark Journey (a really hot female valet), smoking lots of really good weed, and pretending to kick Russian ass around the territory to the cheers of wildly enthusiastic crowds.
Marvin.
I’d like to experience a brain the size of a planet. The depression I can handle, it would make normal life look good.