Okay I had a perfectly working xbox360 phat system. manufacturing date is late (sept) 2009 so its defiantly a keeper. I got mlb 2k12 brand new played it maybe 5 days, then it started freezing at the start up screen. Game says press start, loads all files then freezes. I exchanged the game for a brand new one still did it, got a brand new dvd drive swapped pcbs, played the game for 1 game, (little over a hr) watched some netflix went back to the game and had the same issue. Ive tried unplugging the hard drive and unplugging the Ethernet cable it still freezes everytime right after the loading screen. What else is there to do? It is the only game my xbox freezes with.
I know this topic is old but just in case you're still having problems, have you tried installing the game to the HDD to see if that help? Another thing to try is to start the game up without a profile signed in to see if it's a problem linked to your save file or something.