The laptop in question is running Win7 and is therefore 5-6 years old. The 2 most common sources of problems with computer of that age are virus/malware infection as mentioned by neemo, and hard drive failure. Hard Drive failure is the cause of many of these types of problems about
90% of the time in computers this old. Hard drives are only designed to work 3 years in desktop PCs and only 2 years in laptops. If your Mom hasn't replaced the hard drive in that laptop; you can bet it's begun to fail or has failed completely; in either case a common source of very unusually high disk activity is when bad blocks occur due to physical damage on the drive platter surface. After too many of these, software remapping cannot fix, and you get constant read/write or read errors along with crc (checksum) errors. These are sure indicators of a drive failure.
I would suggest that the first thing you do is download the free
SEATOOLS drive diagnostic from Seagate.com and test that hard drive first. Make sure to run both short and long tests with
SEATOOLS. If
SEATOOLS returns errors on either or both tests, your drive has failed and must be replaced!
Also, the reason you should test your drive now, and not wait further is that you could spend days or weeks trying to track down offending .exe, .bin, or .dll files lurking in your Mom's windows, or even trying to run various av scanners to repair and disinfect any found viruses or malware there. However, if you Mom's hard drive has failed, that's pointless because you'll never resolve the problem until you replace that drive!
It might be a good idea to use an Image Backup program such as
Macrium Reflect and make a backup file or snapshot as the system is now. Here's a link to an easy to follow video on how to use it:
Even though it's working slow, and has high disk activity you can at least backup all here stuff, and if you do find a failed hard drive and get a new one, you can easily put back all her programs, favorites, library folders, and desktop settings in a day versus a complete rebuild from scratch or factory recovery discs which could take 1-3 weeks to do.
We recommend using an external usb hard drive to store the backup file on. 500GB usb externals can be had for
$55-$60 US on ebay.
If you wind up going this route, and the high disk activity is not solved, that means more than likely your Mom had a malware virus infection; and since it's still going to be in the restored disk Image on a brand new hard drive, you'll still have to find it, track it down and remove the offending virus/malware. In this instance I'd recommend you visit our free Virus/Malware sub-forum and let our experts assist you with a customized removal procedure.
Best of luck,
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