Actually, I did pop the new AVGA2 card into the "integrated motherboard" comp along with the arcade hard drive (ended up donating it to my old man - AMD 4000+ and built the new one - AMD 4200+) and although the "sparkles and interference problem" went away when I popped it in, the WMV acceration was still acting funky and I still got the "green" intro. Popped both the new AVGA2 card and hard drive into the new machine w/o integrated graphics and the problem went away.
Perhaps it was the new 4200+ processor then?

I don't think so.
I'd play it safe and not get integrated graphics. After all, you're replacing the graphics anyway right?
~ DeLuSioNaL