This may be a little late...
Zone 5 is perfect for many fruit trees, including apples, pears, quince, apricots, plums, and many others.
When planting apples and other pomes, the rootstock is the most important part. If your nursery can't or won't tell you what rootstock they use, find another nursery.
For apples, the best rootstock that will probably grow well in most of zone 5 areas and grows a tree under 10 ft tall without pruning is Bud 9 (B9). Bud 9 is a fairly new rootstock (1970's), so many nurseries don't carry it yet.
M7 (EMLA 7) is probably the best apple rootstock for most people. It has been used for hundreds of years. Earliest known documentation is from the late 1600's. Probably quite a bit older. With pruning, it can be kept well below 10 ft tall, however, without pruning, it might reach 12 ft on some varieties, so it is considered semi-dwarf. Compact spur (compspur) type apples seldom grow over 8 ft tall on M7.
Stay clear of M26 unless you know for a fact that phytopthora (late blight aka crown rot aka collar rot) is not in your area, otherwise your tree will most likely be dead within 2 years.
If you decide on M7, Miller Nurseries in New York is great. All of their semi-dwarf sized and compspur apples are on M7. They guarantee their plants for a year, even if it dies due to the customers fault. I have never received a bad plant from them, and I've ordered many times. Often the apple trees I have received from them are mature bearing age and have bloomed and fruited the same year that I planted them. A lot of other nurseries charge close to $100 for a bearing age apple tree. They have Golden Sentinel, which is an extremely compact compspur, is scab resistant, takes up very little space, and is loaded with apples that taste like a cross between McIntosh and Golden Delicious.