I like the suggestion of Park City, we (my folks) use to own a Condo in Deer Valley. Park city, when I was younger seemed like a good place for people to go. We are also familiar with it and it isn't to far from Salt Lake. While my wife doesn't ski, she would like to try it once there at least. My mom says she feels "to old", ~70yo, while my dad who is in great shape (stronger than me 32) and is in late 60's would feel bad leaving my mom, unless other people are there. My sister in law doesn't like to ski, but doesn't seem mind doing nothing as she planned a ski trip for her family. My sister and his husband would be into it, though they do have a baby. I don't know if they could get a baby sitter or if the baby could hang out with the non-skiers. We could always get the non-skiers spa packages.
1) Sis + hubby + 1yo baby
2) Bro + wife + 2 active boys
3) mom and dad
4) Wife and I
Thanks for all the suggestions so far.