First, A., let me just say that I lauged out loud when I read about those two staying at your feet while you cook dinner. What a visual! My first son was like that when he was younger. I was his toy. He just wanted me to play with him all the time, and it was exhausting. Now that my boys are 3 1/2 and 1 1/2, they mostly just fight over toys (also very exhausting) but they are definitely interested in their toys.
Maybe they'd be more into their toys if someone played with them with the toys at first. It sounds like you have your hands full between work, kids, grandkids, and household chores. Maybe you can get your older kids to play with your little ones just while you make dinner. Then the little guys will see how to play with those toys and they'll eventually be able to do it on their own. Maybe you're already doing that...
Good luck, anyway! Sounds very trying!