From doing a bit of Googling, I've found out that SMART is a drive diagnostic system, which can be enabled and disabled in the BIOS, and is used to warn of a possible drive problem. The message is telling you it's disabled, which may, in itself, not necessarily mean that a hard drive is about to fail, but if you were to enable it in the BIOS, you may then get a drive error message.
How long have you left it to boot? Some of the comments I read seemed to imply that the message could be there for up to 20 minutes, then the machine boots normally. Obviously, something's not right though, and I'm not sure if it would be a good idea to enable SMART, so I would hold on until Sandra, or someone else good at hardware, sees this and responds.