Weirdly, I find out that my Celeron 2.26 system runs perfectly well with the 3D effects on Linux. (I own a GFX6200). Loads fine.
Okay, we all kow Vista is a resource intensive program, but that's what it's called the future.
I'd try to upgrade your CPU to a Pentium D or PDC (Core 2 Duo's older gen. Pentium Dual-Core (PDC)).