Who Would Win in a Brawl?!

Dr. Horrible wins! Barney would probably just allow Dr. H to bruise him up real good so he could get the ladies to tend to his wounds.

Dr. Horrible!  C’mon, he has a PHd in Horribleness!

Barney doesn’t stand a chance!

Dr. Horrible has a ray that shoot death! Not lasers, actual death!
That being said, I could see Billy trying to get Barney to pick up chicks. It’d be another step towards villainy…

If it was just a fist fight, one on one, no special toys or legal matters, then Barney would win.  Barney has more confidence than Dr. Horrible.  If, however, toys and gadgets were allowed, then Dr. Horrible would take it.  Then, of course, Barney would sue and win in the long run, asuming he survived Dr. Horrible’s death ray.