catress,
I would call to her to get her dog when you see them out without a leash. Once she actually has the dog (if she can even catch it!), then I would start talking about leashing. "Aren't you worried your dog might run in front of a car?" "I'm trying to train my dog to be polite, and when your dog charges at her she feels a need to defend herself and can't learn to be be polite". If she refuses to cooperate on the leash issue, file a report with animal control and ask them to come have a talk with her. If she blows them off, after a few visits they're not going to be so nice about it. And, if for some reason her dog gets hurt, it will be on record that this dog is allowed to run loose and challenge other dogs.
The little dog charges are the hardest to deal with. I do the same as Miabella, where I will yell "NO!" at the charging dog as I back Luna up a step and sidestep halfway in front of her. If it's a big dog, at least I have a decent sized target to block, but those little ones go right through your legs!
Charging dogs that are really serious about wanting a piece of meat are a whole other story, I just have to fly by the seat of my pants when that happens. Thankfully, not often. And when it does, they get reported. No playing nicey-nice with that!
