First of all, to avoid any confrontation like slanging match, I would write her a polite note - or make a poster saying POLITE NOTICE out of a letter - asking that they please keep their noise down, stop the children throwing things over the fence, and have some consideration for you, as you would for them if the situation were reversed. If that doesn't work/help, then by all means if you are living in rented contact the letting agent and/or landlord. We all have the right to live in our homes as we choose, but to have consideration for those around us too, and consider how what we are doing impacts on them. Sadly, so many people these days are mindless of how what they do affects others, or simply don't care. Good luck. I've been in the situation and it's not pleasant at all.
Vision Disturbances: "Aura" Without Headache?

I’d be contacting the landlord. You are entitled to enjoy your home without all that. Living in close proximity to others means that you have to expect a certain amount of reasonable family noise but they sound like they’re taking the absolute p.