Oh, I didn't realize he was referring to Virtual PC. For some reason I seemed to of skimmed over that part.
I would use either VMware Player or Workstation. Both include 3D acceleration and should be able to play simple 3D games like GTAIII or similar and run fairly decently.
While VMware Player is free, VMware Workstation is a commercial product.
Avoid Virtual PC at all costs, it isn't really worth using other than for some simple tasks or a application development environment.
VMware's free VMware player stomps the crap out of Virtual PC, however the emulated graphics are only good for DX8 games and games that don't require DX9 features or Pixel Shading.
Also don't use VMware server, the free VMware server lacks any kind of video acceleration. As mentioned use VMware Player or Vmware Workstation if you want to purchase it.
However the free Vmware Player should be sufficient for what you need.
If you get stuck at all with VMware or don't know how to make VM's in it I can provide you with the freely and legally redistributable files I have archived on my PC to create Virtual Machines.
