World Doesn't Load, Also "Laggy" Sounds and frozen buttons. HELP OR PATCH PLEASE!!!!

So I opened an Iron Door and I noticed the buttons were "frozen" in the open position until I destroyed the door or both buttons. Then sounds began to lag heavily (playing ~1 second after the block was destroyed/created) and I couldn't pick up blocks after I dropped them. Then the game crashed, and now I can't open my world! Thank you in advance, inb4 duplicate, etc, etc.

EDIT 4/18/13 – When I try to open the world, it just takes me back to the title screen! HELP!

Crash report is attached