Here are a consolidation of tips for getting W8 running on VB on an XP Host machine (so 32-bit).
This is a Dell E520, 2-cpu 6400@2.13GHz and 3GB RAM and it is a few years old.
There is an excellent step by step here:
http://www.sysprobs.com/guide-install-w ... virtualbox
That guidance worked almost flawlessly.
In addition to those settings I found that:
1 - I had to increase the RAM set in the VB console from 512 to 1GB
2 - I had to enable the Virtualization setting in the host machine BIOS
3 - In the VB Console settings I set Bridged and the Intel PRO/1000 MT Desktop (otherwise no NIC)
4 - On installing the VB Guest Additions I had to set the compatibility to Windows 7 (yes - it does say that in that guy's tutorial, but I forgot)
...and you don't worry that the Guest Additions stall on the Video part.
Finally I set the NIC to a static IP on the LAN and all works as one might wish.