My camp is at the border of zones 5 & 6 in N.C. Pa. We've had really good success with Liberty, Enterprise, Goldrush, Wolf River, N.Y. 35 "Bonkers" ( to name a few stalwarts of regular apples ). For crabs, our best ones so far are All-Winter-Hangover, Winter Wildlife, Trailman, Dolgo, Kerr & Chestnut - all from SLN. We have lots more varieties of apples and crabs, but these have done well enough that I feel comfortable recommending them.
As for nuts, white, red and chestnut oaks are great for wildlife, but if you're planting new trees - you won't see nuts for 20 to 30 years. Pin oaks will make nuts sooner, but you're still looking at 15 years if you buy 1 B&B tree. I planted a B&B pin oak in my yard 31 years ago, and watched it's progress. We are planting several Chinese chestnuts this spring based on reports of nuts in 6 to 10 years. We hope they come through in 6 years or so. Chinese chestnuts are blight resistant, and are the same chestnuts you buy at the grocery store before the holidays.
Some of the guys on here plant hazlenuts for wildlife. They make smaller nuts sooner - from reports and articles written. We have none of those mainly because bears would destroy them. If we didn't have so many bears, I'd plant hazlenuts in a heartbeat. Good for turkeys and grouse.