/ Do Polish people know a lot about the world ?
This is a type of Polish person - particularly female. I lived in Poland for several years, and knew only nice, well-informed, well-educated people.
This phenomena I know as well. Before I moved to Poland I thought this is how they all where, Polish women (especially) when they move to a different country put themselves on a high shelf. I think it has a lot to do with the looks (yes, polish women are very attractive and when they leave they notice).
Here in Poland they act completely different and have dignity and class.
So to answer your question Polish people are usually very well educated and knows quite a lot of the world but what they don't know I noticed they want to learn.
I'm sorry you live with a she demon and I would recommend you look for a different house don't let her poison your life.