The Installation Began Perfectly

Windows 8 was updated so I downloaded the game onto my laptop. While this isn't at all related to minecraft I played the game on the laptop I am updating windows on, so I won't be able to play it for a long time. While the installation was running perfectly, I noticed an error message that said it was establishing my personal settings. The window has been running on my computer for over an hour now and I don't know when it will end. It will probably be able to function but I'm not sure when. If it's broken, I'll have to figure out a way to fix it, what I would like to do if it was broken is that I could return it to 8.0 with all my data still on it. Minecraft I am open to suggestions and if anyone knows how to fix it, please let me know!