Quelaag is the correct spelling I think. If you're cursed, you could always take the shortcut above the waterwheels that'll lead from Blighttown to New Lando Ruins, which you could use to get to Firelink. From there, you could go through the sewer shortcut and talk to the creepy moss lady to by a purging stone for the curse. After you get some souls of course. Good way to get souls is to help kill bosses in co-op.