virtualbox.org

Is it possible to image my linux host OS, save it, then load that saved image into virtualbox?

Doing so would result in an exact duplicate that I could run as a guest.

Doing so appeals to me. Otherwise, I would have to re-configure the OS settings from memory once running in virtualbox.

Doing it this way would be very slick.

Yep, its called p2v, works for about 90% of the time, when it doesn't you're in for much fun trying to figure out why

Check the Windows Guests section, there's a howto there to help you.