I would have to veto Breckenridge. It is a chaos of crowds that time of year. I live near there and avoid the place when I can for all the crowds, especially the Christmas season surge

In Summit Cty all of the resorts have huge parking lots or garages or both. If you stay in the resort area, there will be buses or shuttle available to take you to a ski base so you would not have to drive. If you are not interest in staying in a resort area or town, Frisco would be a good alternative. Frisco is another town that sits at the mouth of Ten Mile Canyon just off I-70 -- lots of condos. And is about equal distance to Breckenridge, Keystone, and Cooper and all serviced by buses from Frisco. Frisco is the hub of the Summot Cty bus system. Vail is about 30 miles away over Vail pass. All of the close-in, better parking at Breck, Copper, and Vail is charged -- Breck was $20 for the day but its big parking lot is serviced by a gondola directly to base 8 - Breck's original ski base. It is handy.

Frisco is a decent town with some good restaurants. You would use a car more if you stayed in Frisco. When we are in Breck over Christmas the car stays parked. Crowds are intense at that time but if that is the time you can live with it.

Copper has a big tubing hill that is popular. Also at Copper there is a training facility for skiers that has a big form pit for trying stunts. I think the public can have access at certain times -- no experience. Copper is a great ski mountain to learn but it would be so so as a place to stay over Christmas.

My comment about Winter Park being "small" wasn't so much aout ski terrain as the town and things around it--as I had also explained.
Staying in Frisco would not require using a car to get to ski areas as there is a free bus to Copper for instance. Our kids family has house in Frisco and do this all season.
My comment about "Aspen Highlands" was in error--I did mean Buttermilk and it is THE perfect learning area. Wonderful.
I would not buy lift tickets in advance (although I don't know if there will be any limits this season) or from a remote location (outside the area you are skiing). Something might prevent using.
Fmpden's suggestion for managing lessons is good IMO. You have to be good enough to get on and off a lift also.

I have a few thoughts.

Do you have to go at Christmas? I get it, snow and holidays = magical but the days are really short and can be very cold. Ski school starts at 9 a.m. and it is early to get all the gear on and get to the lessons.

I am not a huge fan of Park City. It's really spread out and The Canyons is not the easiest to get around or to get to the ski school area. I don't know about the skis school at Park City side. Deer Valley is fantastic especially if you stay someplace where you can get to the ski lessons. Part of the problem of it is the hotels/resorts are spread around the Mountain and while you might be on the slopes, you might have to take a shuttle but to get to the official base where the ski lessons take place. That can take some time. But because it only allows skiing and limits the number of skiers, Deer Valley can feel a bit easier to handle.

You ought to look at other ski resorts you can get to from Salt Lake City. It's a Delta hub and I'm assuming it's easy to fly there from Atlanta on Delta. Park City is a quick and easy 45 minute drive most days, and some of the other resorts, may be just as easy to get to.

The next thing you need to look at is Epic Pass. This is a Vail Resorts product. They've lowered the price of them through May. If you buy one pass now, they come with ski with a friend and buddy passes. Depending on how many days you are going to ski and how many people, you may only need one pass and use your ski with a friend and buddy passes for everyone else.

But you can buy several different versions of the Epic Pass. If you buy the local pass, you don't get access to Breckenridge, Park City on busy holiday weekends like President's Day. You'll have to look at the exact resorts and dates you want to see if that would limit you.

There are other pass products out there that may offer similar benefits. I do not know as we have a place in Crested Butte which is under Vail Resorts so I buy their Epic pass.

I'd look and see where you can fly directly. That would help me limit my options.

I've been to all of the places you've mentioned above and many more. Aspen all around is my favorite place to ski and visit in the winter. The town, shopping, restaurants, and skiing are outstanding. The only issue is as a beginner the mountain (Ajax) where I'd recommend you stay is not a great place to learn, you would need to take a shuttle from town over to Buttermilk or Snowmass everyday so I would save Aspen until you hit the intermediate level. Jackson Hole and Squaw Valley are even more challenging than Aspen so I'd cross those off the list as well. Vail is very crowded over Christmas time, Breckenridge is an absolute zoo. I would never go back to Breckenridge again over Christmas. Vail is so big and spread out that the large crowds during that time are not nearly as bad as Breckenridge. Park City is the second best all around ski experience behind Aspen in my opinion but due to the lower elevation vs Colorado December is really hit and miss conditions wise out there.

That leaves you to Telluride and one of my other favorite places mentioned earlier Beaver Creek. You really can't go wrong at either place over Christmas time. The scenery at Telluride is drop dead georgous, it will be relatively empty vs the other places over Christmas due to the remote location, and it has an awesome ski town and village. Beaver Creek on the other hand is a little more posh, has the best ski village of anywhere I've been, will be far less crowded than Vail, Breck, or Keystone and is less than 20 minutes from Vail if you want to swing over there for a day or two. We are actually spending time in Aspen and Beaver Creek this year over Christmas and New Years so you'd know how I'd vote! (The terrain is better at Telluride but it's just a big pain in the butt to get to. As a beginner though that won't make any difference to you)

Lastly during that time of year at the places you are considering prices are going to be crazy. I try and use credit card loyalty points to soften the blow and stay at hotels right near the lifts when we go. Once you experience ski on ski off accommodations it's hard to not stay anyway else. You also need to factor in ski lessons and rental gear which is also going to be very expensive too. I'd almost recommend that you all learn how to ski at a small hill first before you do your first trip out west if cost is an issue. I certainly don't like paying over a grand for one day of ski lessons!

After reading your comments above you may also want to consider Keystone too. It is very kid friendly and a great place to learn, they have lots of beginner slopes and I believe kids under 12 ski for free. Also lodging there is not going to be nearly as ridiculous as the other places discussed. Stay in River Run Village if you choose Keystone over Beaver Creek or Telluride. It has nice restaurants and shops in the village and it is about 25 minutes away from the town of Breckenridge if you want to check it out over there a night or two.