In short, a minimum of 6" of compacted gravel or crushed stone, and a inimum of 2" of asphalt.
Optimally, it would be good to have a compacted layer 8 to 10 in. thick, of gravel. 3/4" or less in size. If you have soil that's not stable, geotextile fabric may be necessary under the gravel. Drain pipe (drain tile), which is that 4", perforated pipe that drains around the driveway, may also be in order.
A good start is to talk to homeowners that have had new driveways installed. Find a reputable contractor that has been in your area for a number of years. Tis the season for fly-by-nighters offering all kinds of deals. Make sure you get a written contract specifying the material, the thicknesses, and so on.
Asphalt should be fine for freeze and thaw cycles. (Concrete proponents may differ, but that's OK w/me.) Drainage is key here! (Re-read what I said above about the soil and drainage.) Only seal-coat your driveway when it needs it. That should be done when you see the white of the stone. (That means the asphalt is wearing off.) If you experience cracks and such, there are products in the Home Centers for fixing said problems. There is patching, caulk, and filler. Read the packages carefully to be sure what you want to use for the fix is what the packaging says it's for. Please bear in mind: Your driveway is NOT your dining room. YOu don't eat on it, you don't sleep on it, you don't entertain your guests on it. Your driveway will get all kinds of 'grime' on it. But it's a driveway. Certainly, treat it as a 'member of the family' but don't get carried away with maintaining it like your dining room.
My best to ya and hope this helps.
PS: Just for grins, TRUE story. My neighbor across the stree keeps his home really nice. He does set a 'standard' of sorts for the development. (They dust the mailbox and trash can lids off every day! 7:00am like clockwork.) Anyway, he seal-coated his driveway every year. From 1993 to 1999. In 1999, he had a new 2" of asphalt layed. Why?! Because he treated his driveway like his dining room. He wanted it to look nice. Yup, it looked nice EEEEEVRY year. But guess what was getting tracked into his foyer, and such, every day (by 1999)??? That gewy seal-coating he put down. By '99, he said it was like walking on bubble gum! He did tell me that his contractor said to only coat the driveway 'when it needs it'. He doesn't like the idea of not having a perfect driveway but I told him he ought to take up another hobby, like drinking beer and NOT being a slave to your home. Ciao!