He's not going to get the stuff from storage go get it uourself, put the dishes she bought away and if asked "they sre so nice I put them up for very special occassions."
When ss goes on about how grandma does things: "this is OUR home not grandmas we do things our way."
Expalin to your DH to not inform you how his mommy does things it undermines you as his wife and woman of the house younwill do things your way and if he continues he can go live eith mommy. Difficult mils suck you'll neverbwin with her keep her out of your home as much as possible ignore her and when she attempts to butt in how you do things, just tell her thank you but your help is absolutely not necessary you've been a grown up for a long time but you appreciate her concern.
I'm gonna guess DH and SS were taken care of by her till you came along. She's probably bored and feeling displaced some are doing it from malicious control some are doing it from fear and loss you have to figure out which your working with, it will make it easier to figure out hiw to deal with her.

It sounds like his Mom played the part of " houswife" for him while he was single. Now that y'all are married, MIL needs to quietly & peacefully bow out. Y'all need some time to figure it all out as a new Family. Kinda hard to do when MIL is still trying to overcompensate or veto you & your way of doing things.

In the beginning, my SSs would do that too. "My Mom folds the towels like this". " My Mom doesnt cook with that! Youre doing it all wrong". Blah blah blah!!

Finally one day I had enough!! I explained to them all, DH included, that there are Many ways to do things. Doesnt really make things right or wrong. Just we all have our own preferences & ways to do them. I went on to explain that we were a newly formed Family now- and we have to go forward with our Own new way of doing things. After that day when anyone said "My Mom...." Id simply say " thats great, and Id contnue on doing it MY way!!! Didnt take long for it to stop. I also would say " Thats nice, but is this your Moms house?" Then theyd say, well.. No... Id say, thats right, its not & your Mom has her own house to do as she pleases.

Hang in there, they say the first two yrs are the hardest!! Perhaps with your MIL, you could Thank Her for helping to take care of your DH & SS before you came along. Sounds silly, but maybe you can gently talk to her that way. Hooefully she will be an Ally for you!!!

My SKids pull the "GMa does it this way", "BM does it that way" & I have started replying with "Welcome home!!!" Before my "welcome home" I add in a tentative face, or an "Uhhh..." or whatever strikes my fancy but after saying it, I smile. They normally get a confused "why doesn't she care" look on their faces & they go on their merry way.

Can't believe your DH does that too! How annoying!!! Can you use the above line with him? I think it would be funny

I'm sorry about your MIL. I'm with Neverland...sell the stuff you don't need.

As far as chores go, can you do then when she's not there? I'd fold laundry when she's at her own home. You can also always ask her to have a seat "MIL, have a seat & I'll bring you some tea!" or "MIL, why don't you go relax, I've got this!"

*Sigh* sometimes MIL's can be a huge PITA...

Say "Fuck what your mom/grandma does" - but only in your mind. ignore them.

Or you could be bitchy and say "But this is the right way".

I totally know how you feel. My fiance's mom and sister are visiting us for a month in our tiny apartment and his mom has taken over cooking and grocery shopping, he has commented on how "isnt her coffee/rice/etc better this way?" But I can deal with it cause its temporary.. One of your statements "I didn't marry her, I married him!" I totally agree with but I'm starting to believe its not really true, I'm starting to think that when you marry a person all of their baggage and family crap comes with them.