Double Dragon was the first scrolling beat 'em up to feature simultaneous 2 player action, weapons and end of level bosses and the arcade version is one of the best games ever in my opinion. However for some reason nearly all of the home versions released at the time were poor.
The exception though was the Master System version (which is far superior to the so-so NES version). All the moves, weapons, levels, 2 player option and music are here. The games faithful to the original and is fairly easy until the rock solid last level, but you'll beat it with practice.