Given the choice, I'd take Wendy's over both of them, and it has nothing to do with the fact that my name is Wendy. :P
I always thought you were a dude! :o
I always assumed female, because of the Jupi part. But then again, I used to work for www.sailormoon.org
(before we closed the doors for good), and a Jupi was what we called the SailorJupiter staffers, most of whom were female.
Anyway, I pick McDonald's.
They both suck, IMO, but Burger King is too much of a poser and a copycat to be worth calling the best. Trust me, Hardee's comes out with their Thickburgers (thats a Carl Jr's if you're not in the south), then Burger King turned around and copied them with their angus burgers. And trust me, the BK Angus burgers SUCK. Good fries though.
But, given my choice, I'd go to Arby's. A cheddar melt drowning in horsey sauce is terrific, or an ArbyQ with horsey sauce. Hell, you put enough horse radish sauce on something and I'll eat it :P
Otherwise, its Wendy's with one of their chicken clubs. Although Micky D's has good chicken too.