sometimes if you don't let it shut down completely...it stalls...sometimes it's slow to shut down, but it will...and when it is able to...your next shutdown will be or should be normal
it is basically Vista being polite to a stubborn driver...which in turn is being impolite and not terminating itself
if you do a search you will come upon a registry tweak...
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l]
with mention of: "WaittoKillServiceTimeout"
some will suggest 4 digit numbers...some 15000...anything less than the default 20000
I am only providing info and not telling you what to do
