Problems with my mom?

Yikes, that's a tough one. It's really hard to deal with people like that especially since you can't talk to them rationally because they dont think rationally. I think what you need to do is have a sort of intervention with her, you and your sister and dad need to sit down and have a talk with her and suggest anger managment courses. However, you need to make it very clear that you're on her side and you're not attacking her, because people with anger issues generally think that everyone is deliberately trying to make them angry and bring them down, so handle the situation very delicately.