What enhancement would work best for Fury/Arms Warrior?

Fury and Arms are both dps specs so you want to enchant your weapons (and all your gear for that matter) with enchants that increase dps. Blade Ward is a tank enchant, and lots of enchanters don't even have it since the recipe is a random drop from Ulduar. Mongoose is better for classes that use agility and is also good for tanking, so you don't want that either. Go with something like Berserking or Massacre, they both give attack power, one being static, and the other by proc. Since they are both Wotlk enchants, you should be able to get them pretty cheap. Once you hit lvl85 you might look to get Hurricane and eventually Landslide (costs a fortune atm but is the best melee dps enchant in the game)