Thanks! for your interesting answer.
Now, the problem is more big:
when I load game, every 40÷60 sec game's window reduces to icon and sistem come back to descktop, but play is running: in this way it is not possible to play

.
The same problem I have with rFactor (ISI), BMW3 Challenge (Simbin); no with Toca Race Driver 3, no with World Racing 2, no with CRC 2005.
I'm doing scan with Kaspersky on line to check if there is a virus (http://www.kaspersky.com/virusscanner).
Next step I think to load again DX9.
At the end...

big HD formatting
If somebody has a better idea...
