virtualbox.org

I recently had a motherboard/chipset failure on an XP machine. I bought a new Windows 8 machine, and would like to retrieve some program settings, in addition to the user data.

For the user data I can simply mount the drive and copy the needed files to another drive. But I would like to be able to "boot" the XP drive one last time in order to retrieve some program settings.

Can I use virtualbox for this? If so how? If not do have any other suggestions?

See advanced storage in the users manual.
http://www.virtualbox.org/manual/ch09.html#idp14091280

Rather than using raw disk access you could also P2V the existing image and keep the VM version around for a while. Disk2VHD would be the easiest way to image the old drive, assuming you can still have at least temporary access to it.