Minecraft keeps f*cking crashing Help QUICK!!!?

Okay I have a PC, downloaded a texture pack for fun, and when I re-loaded the game, it crashed...and burned...and I wanted to cry. I have the 1.6.6 version, I think....The latest one, whatever that may be lol. Its not one multiplayer, Im just messing around in single player. I don't know what to do. Ive checked their web page for help but there isn't a damn thing for help. Please, if you have ANY clue as to how I can fix this, I would be forever in your debt. (PLEASE HURRY! I NEED MY FIX!! THE MONSTER CALLS!!! LOL)