Hi Vance , If I could only plant just one apple tree in your zone it would be a SPARTAN . Because that variety is as close to self-pollinating as you can get, so it does not usually require a second tree nearby that blooms at the same time to produce fruit . The fruit is crisp,& sweet with a hint of grape flavor.
They are prolific annual bearers of medium sized deep red to mahogany apples that store 4 or more more months under proper conditions . I rate them tops for both fresh eating and baking . You should try a SPARTAN apple pie !
A dwarfing rootstock will tend to bring them into bearing sooner, take up less space , but , will be less hardy and have a shorter lifespan . A good compromise is the semi-dwarfing rootstocks . I can heartily recommend the rootstock named "Bud 118" . Research these two recomendations for yourself . See if you can find any SPARTAN apples at a grocer and try them out . I think you'll like them . If you are adventurous, in a year or 2 ( when the tree has established you could graft a compatable pollinating variety onto your SPARTAN , and you could have a two-in-one apple tree . I'm pretty sure a HONEYCRISP would work for this , they are absolutely amazing !
Hope this helps you , Burl