re: Witch version?
32 bit Home Premium. Just barely enough to have Aero, or glass.
"Grapes on the violin," one of my college profs would have said. Sure, you can certainly get by without Aero, but why would you want to? :-)
Undoubtedly my fondness for things 3D is coloring my judgement, but I think the UI enhancements in Vista could represent the next step toward something not only cool but useful. We live in a 3D world, after all.
Programmers strive to model the real world...that's a big part of what object-oriented programming is about, of course. 3D interfaces are a continuation of that quest.