How to rename a hard drive?
It seems you have another system - in that you are able to post the question. If it is a mac, you can start the problem system in Target Disk Mode (if it has FireWire), connect it to the working system with a firewire cable and you should be able to change the name remotely.
If you can start in single-user mode (s) that may allow you to bypass the problem.
If you start in verbose-mode, (same link as above), you may be able to see the problem.
If you can start from the Lion recovery disk, or a DVD, that will also allow you to change the drive name.
Finally, if you do get the system restarted, I urge you to check it through Disk Utility (applications > utilities).


I hope this helps.