My dad's parents were Nana and Papa.
My mom's parents were Grandma and Grandpa. Grandpa always tried to be "Grandpa Scoot" but it never caught on. I don't know why he wanted that scoot added.
I called both sets of grandparents maw-maw and paw-paw. However, my kids call my parents mimi and poppy and the in-laws grammy and dad-dad.