Well, you can't compare the games as they are different in pretty much every respect.
Minecraft is ridiculously fun though, I'm playing on peacefull right now (no monsters) as the building is mainly what I enjoy. I started with a small cave on the beach that turned into a rather large underground house. Then a very deep tunnel into a mine complex that had to be closed once I dug too deep and fell into an enormous cave, I wandered around down there for literally hours before I managed to dig myself back up to the surface, breaking ground and seeing the sun shine down on my fave has never been so satisfying.
I've now built a huge castle above my cave home, which is connected to my underground complex with a mindboggling network of tunnels, ladders, staircases and doors. I built a pretty tall tower to be able to see my home easily, then once the castle had become too big for it to matter I built another one, I'd like to make it taller, but the game won't let me
The clouds are actually floating through it at about the middle.
Oh, and I made giant floating letters with torches on them that spells "Urge" in the sky. Because I'm humble like that.
Can Skyrim beat that kind of fun? There's no way to say honestly, as I said the games are so different. I love creating stuff, so I don't know if Skyrim will beat the feeling of having built a huge castle by hand, but it'll probably be awesome in other respects.