1) Hiya toots. (Grandma, huh? Young kid. Wait till you worry about the grandkid's wife.)
And welcome to the forum.
2) I'd go with Straight Talk. Tracfone is more expensive if you plan to actually use the phone.
3) An Android phone IS a smartphone. But if you can use a computer (you're here, so I guess you can), you can learn to use a smartphone. Mrs. Rukbat also thought all she wanted was talking to people. Now she texts the kids all day, plays Bingo, on and on. Didn't need one, but once she got one ...
4) Pick the carrier first. AT&T, Sprint, TMobile or Verizon. Ask around, see which of your friends has problems with coverage in the places you're going to be and who their carrier is. The best phone, with no coverage, is a paper weight.
Straight Talk uses all 4 carriers, so pick the one you want, THEN pick the phone. If AT&T or TMobile are best for you, you can choose almost any phone. For Verizon and Sprint, you pretty much have to use one of their phones (or one branded Straight Talk, but really a Verizon or Sprint phone).
But pick the carrier first - that makes or breaks your cellphone experience.
Oh, and with ST, texting (within reasonable limits - spend at least a FEW hours a day sleeping) is unlimited, so you can gab with all the kids all of the time. (And talk the family into using Cozi calendar if they don't already. It makes keeping track of who has to pick up whom when from what much easier. And the free version does the job fine.)