We got the potatoes in! We picked up seed potatoes in a very small town in an even smaller hardware store. But it catered to gardeners with inexpensive seed potatoes that grow well in this area. We passed it on the way home from purchasing a third, fourth, sixth, or twelvth-hand sprayer for the tractor. (It needs work!) We stopped by the store because small town hardware stores are on the list of favorite things to experience. This was a cool one with no end of empty hornet nests hanging from the ceiling, along with various turkey tail feather sprays. It had a little bit of everything, as small town hardware stores do. I went back to the truck after choosing my potatoes and some nails-by-the-pound. Satisfied.
So the story on growing potatoes from seed potatoes vs grocery potatoes is this: Grocery potatoes are sometimes, or maybe usually, treated with something that slows the growth of the buds. If your grocery potatoes are budding anyway, they will grow. But the seed potatoes are better becuase they are not treated, and more importantly, they are usually certified disease free.
I left the potatoes in the bag in a warm spot so they would start to bud. Plus it has been too cold outside to plant. Potatoes like cool weather, but the plants themselves do not like freezing temperatures. I like to cut the potatoes into sets. 
They can be planted whole, but cut into pieces I get more plants! Each piece of potato needs to have a couple of eyes or so. I left them out for a couple of days so the cut sides would get a dry skin. Some say that helps the potato stay healthy and not rot. Some say plant right away because the cut piece looses moisture that it needs to grow.
Potatoes are easy to grow and there are several planting options. I read about planting in a large trash barrel, but most people were disappointed with their yields. (I wonder if that is a heat issue.) I also saw some five gallon buckets planted with potatoes in a suburban backyard. He got good results. We have previously planted them in dirt in raised beds and gotten good results. Another method is to lay the sets on the ground and cover them with hay. That’s what we did this year.
Because potatoes are heavy feeders, we put down six inches of rich soil. Then put the sets, eyes up, on the compost/soil and covered them all with six inches of wheat straw. It is really still too cold so we covered the lot with thin painter’s plastic. The forecast looks like freezing temperatures should end in a week. That should be before any of the greenery comes up through the straw, and hopefully before the whole thing molds from the trapped moisture! I’ll let you know what happens.