[Dynamithix]

Well, if you want Ornstein's armour and weapon, it's going to be a bit harder because after you kill one, the one that's left, in this case Smough, will turn into a stronger form and has more powerful attacks. On my first playthrough, I beat Smough first and then Ornstein, I thought that was a bit easier.

But yeah, they're pretty much the hardest boss fight in the game so once you're over that, you can kill pretty much every other boss in the game no trouble.

Protip: Their weakness is fire and if you need to heal/use sorceries, go to cover behind the pillars. Even Smough can't usually ram you through the pillars (even if they're broken already).

Also, don't put much levels to Resistance, that's pretty much the useless skill in the game as certain armours cover its purpose. What kind of a character do you have?