World not being generated and constant freezing on start.

When I opened Minecraft everything seemed to be fine. I go to create a world, press the button and nothing... I see that the file is in the menu but when I click on it my game freezes and crashes (or I have to close it in task manager). I eventually get the world to generate but when I try another one, it simply doesn't appear anywhere. Now whenever I open the game it freezes my entire computer, I checked the processes in my task manager and it seems that Service Host's process (Connected Devices) is using up abot 50% of my CPU. The thing was I turned the multiplayer option off, so maybe something with Xbox live?

This isn't normal since my computer handles most graphically intenses game pretty well. We all know that Minecraft isn't that taxing on a system so I have no idea why this wierd behavior is happening.