2nd fix: See if you have "Use VBOs" enabled in your settings. On my old, crappy, laptop, I was unable to play with VBOs enabled. The same thing would happen to me, where I'd try to join a Singleplayer world/Multiplayer server, where it would freeze and then crash.
If neither of these work, then I'm sorry, I can't help. Hopefully someone else can, if that's the case.