Black Ops Troble....HELP

[stevesteveo6]

Every time i log onto black ops. a message comes up that says "call of duty black ops servers are down". and evrey time i try to play multi player the error message for disk unreadable comes up. or my xbox just freezes, or it will simply just say the servers are down. so i thought it was the disk, so i exchanged it at bestbuy for a new one, and it still does the exact same thing. I made a free 1 month account and when i play on it it lets me play multi player zombies but still freezes when i try to play actual multiplayer. but the error message about the servers being down never comes up on this new account.....idk what it is thats wrong but i know its not the disk. any ideas?