The Nook is from Barnes and Noble. I personally like it better than the kindle. We have two nook first editions, nook simple touch and a nook tablet.
Hubby uses the nook tablet, the one of the first editions is put away for now. My oldest son reads the other first edition and I have the simple touch.
The text on the nook is able to be adjusted bigger and smaller as well as how wide the text goes on the page, and how much space between the lines.
I find that sometimes the people at the Best Buy really don't have a clue and you need to do some independent research as well. BUT it will at least give you a chance to handle them. If you have a Barnes and Noble near you, go in there and talk to them about the Nook if you want more info.
I don't know about Kindle, but we have extra warranties on our nooks that go above and beyond what is "standard" and covers drops and spills as well. So if you drop it and crack the screen, they will replace it.
This is the nook simple touch - BARNES & NOBLE | NOOK Simple Touch
And this is the nook simple touch with backlight (haven't actually seen one of these in person, but I get the feeling you would get the same eye strain with it being backlit, but not 100% on that) - BARNES & NOBLE | NOOK Simple Touch