It's quite likely that someone has compromised your logon details and used it to send out spam, which would get it disabled. This is also a very common issue with Hotmail accounts and I personally know a few people that had their account compromised. The most likely way this happens is when one using a PC that was infected with a keylogger.
I would suggest try e-mailing that address again, as only they can unblock it.
Otherwise, try setting up a new account on another social networking website such as Google Buzz or MySpace, etc. Facebook is not the only social network website out there.