When I try to open up one of my single player worlds, the game crashes.

The game crashes when trying to open up a world

What I expected to happen was...:
that the world would open up properly

What actually happened was...:
the game closes and a window from the log in screen pops up and says "Uhoh, it looks like the game has crashed! Sorry for the inconvenience "

Steps to Reproduce:
1. Open up Minecraft and log in
2. Go into the Single player menu
3. Go into any selected world