laptop running slow/programs freeze

My daughter recently returned a laptop ( a Toshiba with 64 bit Home Premium SP1) she had "borrowed" awhile back. She said it was running slow and acting weird. This was prior to forgetting her password.

I was able to gain access using the rescue disk. What she said about performance is true. It boots up fine, but is slow shutting down. Programs freeze up frequently and the browser is slow to load. It has not been used in several months. There are 100 + updates waiting.

I did a few things:

- reinstalled and used CCleaner.
- installed and ran the current version of Malwarebytes Antimalware. The full scan found 1 PUP (Open Candy)
- ran SFC Scannow and there were errors, but they are now fixed
- ran CHK Disc with repair options enabled. It said the volume was clean
- removed and reinstalled the AV, MSE. It installed and updated but it would not complete a scan.

After using the update tool, I also tried downloading and installing the Windows Updates twice. It sat for hours with 0% downloaded. However, when I shut it down the second time it proceeded to install 7 updates without my permission.

I would like some assistance in trying to fix the performance as I would prefer not to do a reinstall if possible. Thanks.

I have not received a response to this post. Should it be posted in another thread?