I installed XP32 in my Fusion installation. I believe Fusion supports the 64-bit versions of both XP and Windows (but you should visit vmware.com to confirm). I have allocated my RAM 1 and 1. For the 32 bit version of XP, many folks say 512 is sufficient but I have not noticed any issues going 1 and 1, and since you can change it on the fly, you can tweak away at it. I use Office (Student/teacher edition) under Fusion and it works seamlessly, no issues at all. It's especially valuable in Unity where I can just launch Word on my Mac desktop (or excel or powerpoint) without seeing the whole windows desktop. Piece of cake.
Note that in the new Fusion 2.0 Beta 2 release, you get even better integration and more expansive Unity features.
Cheers
Note that in the new Fusion 2.0 Beta 2 release, you get even better integration and more expansive Unity features.
Cheers