Improper shutdown can screw Windows up so it won't startup properly next time, or it can cause errors to the filing system, but I've never heard or experienced it causing any kind of hardware damage or creating bad sectors on the hard drive in all my 20 years of using and fixing computers.
Old means how old?? I have segate ST3500418AS which is 2.5years old. Is this have this security?
If it's sata, then no worries. We're talking ~10 years ago or so. Most drives that old are dead or replaced by now. I do have some drives that old and operational, but I'd expect most people have all newer drives. I just threw that answer out there just in case you did have an old drive.
I should have mentioned that although the heads will park, having power cut from a brownout or blackout and the ensuing power spike when power is restored may cause problems to the drive electronics itself. A battery backup can help prevent this.