the glass affect has nothing to do with which bit OS u have its about your video card, x86 beta 2 is the better
more drivers are supported along with better program compactability and it is only recomended to install the x64 based OS if you have a x64 proccessor.
so id say install the x86 version (i got it) and see if your video card can handle "aero"
I alos hope ur not planning on using vista as ur main OS