Check your virtualbox settings. You should be able to get 128mb for video, 256mb if you enable 2d/3d settings. That should give you true color. Aero doesn't like to run when running Windows in virtualbox but the graphic resolution shouldn't be low.
That's ok. I prefer to access all of my OS versions through RDP windows. I'm not interested in running them through the virtual box interface. But thanks for the info anyway.