I think that's difficult another program affecting the shutdown, because when I close a program, I wait for the end of this process and the "clean" of his data from Virtual Memory.
But, these are the programs I was running before shutdown the PC:
Opera Browser 9.0 (build 8502)
Winamp 5.24
CachemanXP 1.1
S2KControl (a software that decrease the processor clock when i don't need processing power)
Kaspersky Antivirus 6.0.299
And, now I've remember, My WLM was been patched with
A-Patch, this can affect?
Thank You!