I usually just try and have as little to do with the parents as possible... I really don't like dealing with them.
My mom never really talked to my coach, she would just check in to see how I was doing and talk about expenses, etc. The parents that do that don't annoy me.
There are two kinds that I cannot stand. The ones that are SUPER involved and want to come watch their kid at every practice and be front row at every competition and are constantly asking me how their kid is doing annoy the hell out of me. If you seriously want to manage everything yourself then you should coach your kid yourself. I was SO happy my mom was never the equivelent of a gymnastics stage-mom, and it made me much more responsible and a better gymnast. I also can't stand the parents that come in and blame me for their kid not doing well-- no matter how good a coach you have if you do not work your ass off and practice you are not going to be good. Coaches do not have magic powers, and I definitely do not! 8)
After the last altercation where this mom bitched me out twice, I just didn't really respond and told my boss about it and from now on she hasn't come up to me and has just been dealing with him... I think that's the best way to go, mom's never really have any respect for me because everyone thinks I'm like sixteen years old-- I look super young.