I don't know how you get into the logs on Vista, but if there's a hard drive problem you may see clues of it in the system event log.
If you have any valuable data on this laptop that hasn't been backed up, back it up. Be conscious of the possibility of malware infecting any USB drives that you plug into it though.. that could be a bit of a mess.
If you've never made the recovery discs for this laptop, do that promptly. The procedure varies by laptop, but manufacturer should have instructions.
*If* the hard drive is failing then you want these things done before it's too late.
Once the recovery discs and personal files are secure:
Try running a long surface scan with a hard drive diagnostic utility. This will take hours. I like HDAT2, but each manufacturer has their own utilities also. There's a package you can download called the "Ultimate Boot CD" which has a bunch of useful utilities on it, including tools for testing hard drives. It's a handy CD to have around.
https://www.ultimatebootcd.com/
Do not test the hard drive until after you have backed up files and created recovery discs. The stress of testing the drive could kill it if it's already in the process of dying.
If the hard drive tests good, next thing I'd try would be one of the many bootable linux discs. A popular example that will support most hardware would be Linux Mint. You don't need to install it, just boot the disc and it will give you a GUI to click around in. If that disc runs without the freezing issues, then the problem in Windows is software, not hardware. Most likely malware related.
I hate trying to salvage an infected machine, so personally at that point I'd do a clean reinstall of Windows. Most laptops have a boot option, probably displayed on the initial splash screen, which will let you restore the factory Windows install.
Make sure you make backups of everything you care about first, because that restore function will literally put it back to how it was on Day 1.
The ability to use that restore function depends on recovery data which was left on the hard drive from the factory. All hard drives die eventually, so it's a good idea to make a set of restore discs so that you are not dependent upon that recovery partition. How to make those restore discs depends on the laptop, but the manufacturer should have instructions.
