J.L.
Sounds like these friends are clueless...Let's start with the easiest one. If they are coming to parties that are supposed to be potluck or everyone brings something to pass I would clearly be bold enough to ask HER to bring something specific....Like so and so is bring the fruit another is bring the chips and dip....Jane, I need you to bring the veggies and just before the party remind her....Secondly kids will be kids, have a policy that their kids don't bring over toys so there are no arguments and also so they don't get broken or lost with your kid's toys. As far as them staying late...If they are that inept about etiquette then you need to be bold and say. It was so nice of you to come and visit but now its time to go...I have to put Johnny and Suzzie to bed and it has been a long day...Or you simply go over to their place and leave when you want to...Easy enough.
As far as discipline with the kids you can only discipline your kids and not theirs. For your birthday, if those kids act up, then those parents will have to deal with it not you. If it was important for you to celebrate your birthday without the commotion then it should have been with your DH and kids only or clearly and adult evening where you hired a sitter so you would not have had to deal with the drama.