I heard that some people can hack your 360 or Live account. Is this true? If so, how do they do it? Cause someone just gave me a code to download a game off of the marketplace, could they be a hacker? Thanks.

no

r u kidding, yes u can get ur xbox 360 hacked, it happened to me the other day and it sucksssss! they change ur password, and what happened to me is that they bought 120 dollars worth of microsoft points to my account.