If I'm baking with apples, like a pie or an apple crisp, I'm apt to use a combination. My ideal is a mix of Granny Smiths and Fujis. That gets a good sweet-tart mix and they're available year-round. I use a 2 to 1 ratio of Granny Smith to Fuji. That gets a great apple flavor without it being too tart.
For baking whole apples, I like the Ida Red or a York. Fujis are pretty good for this, too. You want a nice looking apple, with a sturdy structure and good apple-y flavor. In general, these flavors fit the bill.
For eating out of hand, I like Fujis and Galas, along with Braeburns. They're nice and crisp, with a little tartness, but are more on the sweet side.