If you want to know in exquisite detail absolutely everything about the functioning of your hard disk--and want to be warned if there's a danger of crashing--you'll want to give DriveSitter Pro a try. It delves deep into your hard disk and reports on a mind-boggling amount of information. Be aware, though, that much of the information will be incomprehensible to the uninitiated, and that if you don't need this level of detail, the registration price of $25 is overkill.
DriveSitter Pro does a very good job of starting with the basics, showing you basic such as your disk manufacturer, capacity, free space, type of file system (NTFS or FAT), serial number, and more. In addition, it reports on the overall health and performance of your hard disk, and even provides you the current temperature, so that you can be warned if it's in danger of overheating or crashing.
That, though, is just the beginning. You'll also see exquisitely detailed information about disk performance and other metrics, most of which you may or may not understand, such as Raw Read Error Rate, Spin-up Time, and Power-ups Count. And it offers much more than that, with weird-sounding statistics such as Offline Uncorrectable Sector Count. And there are plenty of statistics that are merely listed as "unknown attribute."
Note that in order for DriveSitter to get the most information and statistics possible from your drive, the drive must adhere to S.M.A.R.T. (Self-Monitoring Analysis and Reporting Technology ) hard disk technology. Most newer hard disks do, but the best way to find out is to install this software, and see what it finds out.
If you understand these kinds of statistics, you'll most likely love DriveSitter Pro. If not, you may not be a fan, although its ability to watch the health of your hard disk is useful even for those who don't understand most of the arcane statistics. There is free software (such as Active@ Hard Disk Monitor) that performs similar tasks, so if you don't need to delve extremely deeply, you'll be just as well off with a freebie. But for deep-down analysis, DriveSitter Pro is superior.