VirtualBox - 64 bit OS on a 32 bit host - Pros and Cons
Solution 1:
Yes, you can run a 64-Bit guest on a 32-Bit host using VirtualBox.
Moreover, I have tested the performance of a 64-Bit guest system on 64-Bit and 32-Bit hosts and for my specific loads there is no significant difference.
Sure, 64-Bit guest on a 64-Bit host feel slightly faster, but according to my measurements it's about 5% difference.
Just make sure you have enough memory on the host (4GB total will be reported as 3.5 GB for a 32Bit XP).