when i press play on the 1.2 minecraft it says that it looks like this has crashed. i really cant read the stuff it shows me but i dont know what to do

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What I expected to happen was i see the mojang label to pop up and i can choose singleplayer or multiplayer
Describe what you thought should happen here

What actually happened was that it says this game has crashed
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Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
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