Xbox360 locking up. (need suggestions)

I recently purchased need for speed Undercove but when i try to play the game it lets me start a race then lockes up so hard that i have to restart it.

it even does it with Need for speed carbon and prostreet. to be honest i dont understand it bc i can install the game to my hdd and it works perfectly

but when i just play it from the disc thats when it locks up on me. and i dont want to install it to my hdd bc i wont be playing it as often as i do with the ther games i own.

any idesw. bc it works perfectly on every game i have except the nfs undercover, prostreet and carbon.

thanks for your help.