Both are great mountains. Lodge in Breck and drive over to keystone a couple days during your trip.
Places to eat in Breck: Downstairs at Erics (baked wings), Giampetros (Calzones), Rasta Pasta (Chicken Montego Bay dish), Rita's (Margaritas), Mi Casa (Dope happy hour). Breckenridge Brewery (brew pub). Safest order at any restaurant: hard to find a bad burger in CO.
Places to eat in Keystone are usually over in Dillion: Dillion Dam Brewery (Brew pub), Red Mtn Grill, Arapahoe Cafe, Pug Ryans (brew pub)
Best breakfast joints: Breck - Clint's Bagel shop, Columbine Cafe, Daylight Donuts. Dillion - Blue Moon Bakery.
Good luck and enjoy your trip man. Make sure you warm up to the jumps, we got all sizes here and there is no need to bust yourself up on the trip.
If you're here on the weekends, I suggest taking the trek over to Vail or Beaver Creek. It'll be about an hour drive for you, but totally worth getting out of the crowd the rushes up here. If that's too far, Copper Mtn gets less traffic and is near Breck. They have a good park and just opened some great skiing terrain.