Most people like those adjustable chairs on wheels, because you can fit them to your body size. I hate them. For me, there's nothing better than a chair that's NOT on wheels, one of those old-fashioned wooden straight-backed (and I do mean straight and not slanted backward, the way they all are now) chairs with a padded seat. It cushions your bottom and supports your back. You can also move around on it so your weight is arranged differently according to how your back feels. You can't reposition yourself in a chair with arms.
For you, get a chair that's comfortable when you first sit in it. Test to make sure you're sitting straight as you work, with your lower arms parallel to the ground when they're on the table. Again, make sure it's a chair you can reposition yourself in from time to time, too.
I agree with the person who said to get up and move around every so often. That's important, too.