Chicago to West in 10 days

My wife and I plan to leave Chicago Dec. 26, want to spend a few days in Vegas and maybe a day or two in LA. We have to be back in Chicago by Jan. 4. I don't mind taking a few days and sightseeing along the way (maybe even get a day of skiing in the Rockies in). One way, probably return, we will drive through in 2 days. THe other is open, as long as we have some time to play in Vegas and LA.

Any suggestions for itineraries, routes, stops, etc.

We drive a four wheel drive Jeep Grand Cherokee, so roads (as long as they aren't closed) won't be a huge problem.