Thanks for the info Falsey; I'm happy to say that I just beat him and managed to clock onto the tell for the ghost sword. It took all 15 of my Estus flasks to take out the small and big skeletons. I tried avoiding the big ones but they decided to join in as I ran from Nito's big black wave attack, though I did end up running right into them to avoid that
. After all the skeletons were gone I had a tense moment as Nito caught me with just over half my health to do that attack where he has control of you and saps your health. Luckily I had a little health left and used some humanity to keep me going. I got a bit cocky going for the last two strikes with the Astoras sword and he managed to hit me. I thought that I was done for but the recovery time after the attack gave me the chance I needed to finish him.
I'm going to explore the gold gate that opened in Arnor Londo next as I know that the Four Kings await me in New Londo Ruins and I've heard enough about them to leave them for now.