It appears that the ext2fsd solution has not been updated on over 2 years, and has outstanding known bugs that indicate they create data corruption, so I would be cautious about that approach.
I think you would be be better off accessing the filesystem from a native OS. I would suggest that you prepare a bootable image of the Ubuntu desktop installer ISO for the version you have/had installed on the dead PC, and use that to boot your Windows 8 PC.
- On the Windows 8 machine, download the appropriate image from Ubuntu.
- On the Windows 8 machine, either burn the image to a CD/DVD, or make a bootable image on a USB/flash device (I prefer the PenDrive tool on Windows).
- Power down the Windows 8 machine and attach the dead Ubuntu machine's disk via SATA (before power up) or USB (before or after).
- Insert the CD/DVD/USB/flashdrive in the Windows 8 machine.
- Power up the Windows 8 machine; when it starts, be sure to configure the BIOS to boot from CD/DVD or "removable device" (USB/Flash) before the local HDD, or choose it from the boot-time BIOS selection.
- At the Ubuntu Live Welcome screen, select "Try Ubuntu", not "Install Ubuntu", and allow the system to load.
- Look for dead system's disk on the Live Ubuntu's desktop/Nautilus/mount list.
- Navigate to the files on the old linux drive that you want to recover, and copy them to a partition on the Windows 8 machine, a USB/flash device, or network storage.
- Shutdown the Live Ubuntu image and remove the CD/DVD/USB/flash device from the Windows system.
- Restart the Windows machine under Windows 8 and access the files from the location you copied them to.