If going by powers alone, Superman wouldn't even need to strategize to defeat Batman. But how often do you see Superman go out against a human? If they were new to each other, he would probably give Batman at least a chance; actually, he's even given powerhouses a chance (i.e. he gave Doomsday a cheap shot first hit showing how much confidence Superman has for his durability).
However, unless Batman happens to have kryptonite with him [in an impromptu fight], Superman will take him down as softly as he can as he is aware of what Batman is capable of.
This thread was already done at the beginning of the month:
http://www.killermovies.com/forums/showthread.php?s=&threadid=319295&highlight=Batman+vs+Superman
Paola should be merging this one soon.
But before she merges, I would just like to shed some light to this battle.
Firstly, he would "need" Kryptonite just to bring Superman to his level, which is a handicap in itself, secondly on a straight up level Superman could "decapitate" Bruce Wayne with one blow, fry him with heat vision, run circles around him with his superior speed, or fly him into space and just leave him there, the possibilities for Superman beating Batman are endless, I feel my creative juices just flowing by thinking of the various ways..
Giving Batman kryptonite isn't fair, giving one guy the others mortal weakness, and even with the green rock it would be a task in itself..Superman wins this on so many levels that you HAVE to be a batman fan to say otherwise...