Hey, I have the exact same problem. Yesterday I noticed that my acer
aspire 6935, which indeed can run aero, was gone to the basic vista
theme or color arrangement if you could say so. It's not a huge problem
which causes much confusion, but I want my aero theme back. I've tried
to update my score and then look whether it was there or not, it wasn't.
I've looked for it in C:\Windows\Resources\Themes and it's right there.
I tried to open it and it shows Windows Vista in themesettings/options
(I'm from Denmark and don't know the english name of it). I've tried it
before and it also tricked me in the start, but then I magically found a
way to figure it out, I don't remember that way.