Mincraft has crashed! error whenever I try to play the demo version

I get the Minecraft has Crashed error whenever I try to play the demo version.

I run the application in the browser and it get as fdar as the start screen.

Then I click on "Play Demo World"

The I get the crash screen and it also says:

"Minecraft has stopped running because it encountered a problem; Rendering screen"

I will attach the crash report below.

I have tried downloading it, playing it full screen and trying in the 64bit browser and get the same error everytime.

Please can you help. If this works I will probably buy the game but need confidence it will work.