Money Makes the Hero

"The best power ever - cold hard cash!"

Ok, people are talking about this in terms of who would win in a fight so I guess I'll throw my two cents in. The three factors affecting the fight would be capabilities, preparation and enviroment.

Capabilities What the heroes are capable of.
In terms of brute force suited up Iron Man would take Batman down, simple as that. I. M. is strong, has long range weapons and is damn hard to hurt. Admittedly B. is physically as tough as a man can be, agile and has his own array of gadgets but this will do little for him untill I. M. is out of that suit. Mentally both are geniuses but I would perhaps side with B. for quick thinking, I. M. is a wonderful weapons designer but for on the ground tactical thinking B. 'the worlds greatest detective' outclasses him. Theres also the question of how far they'd both be willing to go, Batman refuses to wield a gun or kill but I.M. wears one and is comfortable killing, on the other hand B. will be able to do a lot of nasty things without crossing his strict moral code.

Preparation How much time the heroes have before the fight.
B. would obviously win in a fight with I.M. if neither were able to make it to their suits due to location or time constraints.
If preparation time was about ten minutes or more than I.M. would win, we have already established that his capabilities are greater than B.
If our heroes have a couple of days or hours than B. might draw an advantage, able to adapt or craft gadgets, EMP bombs, special gasses and liquids to take out his opponent faster than Iron Man can create weaponry.
A longer time period than that and we get a game of intellectual cat and mouse with both our heroes building counters to counters of weapons, hard to predict who would benefit.

Enviroment Where the fight takes place.
On an open battlefield I.M. would be at advantage. B. would benefit most from a dark, enclosed enviroment, large enough for him to stay hidden but small enough to be able to mount an attack.

You decide.