I enjoy both games. If you want the storyline to be the main focus of your adventure and don't care about exploring on your own, then the Witcher 2 definitely has that going for it.
However, if you like the open-ended type of adventure that allows you to follow the main storyline at your own pace and do whatever you feel like doing, love to explore and see the "sites" of the land, then Skyrim is the one for that.
I play both!
i couldnt agree more