After launching minecraft, the mojang screen appears and after waiting for a while it will crash and take me to a crash report screen in the launcher.

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Open Minecraft
2. ...Play
3. ...Mojang screen
4. Waiting
5.Waiting and more waiting
crash
crash report screen