TriggerFinger

Both tools (Memtest and HDD diagnostic) come as ISO files. These can make a bootable CD. Since they are bootable CD, they can run regardless what OS is installed. Just make sure you can boot from your CD drive. You can do this by changing boot sequence in BIOS settings or by choosing a boot device during start up.

As for the HDD diagnostic tool, it is encouraged that you run the diagnostic for your brand of HDD. Unfortunately the list on the link on my sig (HDD Diagnostic Tools) does NOT include Toshiba. If you are using Toshiba, use Hitachi Drive Fitness Test utility (d/load from same page).