If you select a mid-Colorado resort (Copper, Beaver Creek, Vail, Aspen, Keystone, etc.) and decide to fly into Denver, DO NOT plan to return to Denver on Sunday afternoon/evening. The traffic jam on the interstate has to be experienced to be believed, but you're much better just believing me than experiencing it. If you can fly into the Eagle airport without a huge increase in airfare, this is a much better bet if you have to leave on Sunday.
Also, it can never hurt to know the future, so here's my prophecy: Your little one-weekend "let's just see what it's like" experiment will result in a lifelong addiction. If you suspect there's any chance I could be right, it might be worth considering that the Vail-owned resorts (includes Vail, obviously, as well as Breckenridge, Keystone, and Beaver Creek in CO and Heavenly at lake Tahoe) have a frequent-visitor program called Peaks. If you choose one of these resorts, then definitely sign up for Peaks before you get there because lift tickets and lessons and an on-resort stay for two people on a long weekend could very well earn you enough points for at least a free lift ticket next year.
Also, don't underestimate the value of good quality snow in making you a good skier. I learned on poor snow and still got addicted, but it's amazing how much better you'll be on good snow. This is especially important when learning to ski and when you're deciding whether the enjoyment is worth the effort. Despite the many reasons to consider the Alps (later, perhaps), reliably good snow is not among them. For reliably good quality snow, Utah may be best, followed by Colorado. And check the elevation of the beginner slopes. As mentioned with regard to Whistler, most bunny slopes are at the base of the mountain, where snow conditions are unreliable, even at otherwise good resorts sometimes. Heavenly Valley at Lake Tahoe might be an option to consider with this in mind, since there's a nice beginner's area well up the mountain (though I'm not sure if this is where the beginner lessons occur).