In addition to the three resorts, you should also consider Park City Main Street and Newpark out at Kimball Junction. Grand Summit at Canyons is probably the most family friendly resort hotel with dining, pool, etc. at reasonable price of the three resorts. Canyons has great zip lining, mountain biking, hiking, gondola ride, etc. Some restaurants. PCMR has most activities with significant on-mountain activities, alpine slide, coaster, horseback, minigolf, etc. Marriott Mountainside best hotel option. Fairly vibrant resort plaza. Close to Main Street. DV is quieter. Silver Lake better option than Snow Park. Mountain biking, chairlift rides, horseback. Some dining. Goldener Hirsch is nice.
Main Street offers most activity with easy access to PCMR. Marriott Summit Watch is best choice. Tons of restaurants, shops. Newpark Resort is also a great option. Small resort hotel, great pizza restaurant, tons of other restaurants, bowling alley, movie theaters, etc. Live music Thursdays in resort plaza.