First of all, what you're describing sounds exactly like most families I've met in my life. Just sounds like a mainstream American family to me. It seems you're looking for reasons to dislike her, which I think happens often with in-law situations. You are doing to her exactly what you say she does to you in your sentence about being jealous. If your husband is on the same page, it should be easy to simply spend less time around her.
She will figure that out when her son starts school. She doesn't sound like she is going to take any good advice. Especially from you, since it sounds like she already doesn't like you. Live and let live at this point, unless you think you can say something gently enough to not ruffle feathers.
I'd also like to point out that kids are all different, especially preschool age, and especially boys and girls at preschool age. I love art, I was the quiet kid who would just sit with coloring books for hours. Both of my sons hate drawing, coloring, and writing. I have tried sooooo hard to encourage them in art, to no avail. They would rather tussle with each other like bighorn sheep. Ugh. What did I do wrong? Nothing! They are just boys!
I don't know who've you all met but sorry, I dont think being a absolute brat and bad mom without manners is typical of mainstream american families! And if they are then that is really sad. I am not looking for REASONS to dislike them, they make it pretty easy to dislike them. Not sure what you mean about the jealousy comment, I don't diss her kid to her face like she does to mine. I've kept my mouth shut until this post! Anyway, I was more interested in feedback about how certain things (too much tv and not enough variety with playthings) can cause issues in development.
Just because she chooses to parent differently than you does not make her a bad mom and it seems extremely harsh to call him an "absolute brat" especially since the behaviors you described are pretty typical in most toddlers and preschoolers at one time or another.
Welcome to Mothering!
I am concerned because of how you seem to be defining the issue. You said, "Anyway, I was more interested in feedback about how certain things (too much tv and not enough variety with playthings) can cause issues in development." I see these issues as something to take into consideration when deciding how to parent my own children -- but totally not my business when it comes to other people's children.
I think the issue that you need to be concerned about is completely different. You said, "Yet she is incredibly harsh on my kids..." and, from this statement, it sounds like she is being unkind to your children. You also said, "...she tries to make herself feel better by putting me and my children down." Being unkind to my children and putting my children and me down are totally unacceptable behaviors.
I also simply wouldn't hang out with anyone whom I didn't enjoy being with, and this relationship doesn't sound like it's any fun for you or your children. All the other stuff about her being a bad mom or being jealous of you is totally irrelevant...I think you should absolutely feel okay about letting this relationship phase out simply based on her treatment of you and your children.
Or if she's a relative and you can't phase her out, you could just see her at family get-togethers, but intervene or even leave if she starts being mean to you or your kids....and if the get-together's at your house, let her know if the way she's speaking to you or your children, or the way she's allowing her son to behave in your house, is unacceptable, and then ask them to leave if the behavior continues.