These can be difficult to figure out.
First I suggest unplugging all USB devices. Sometimes certain devices can keep you computer from going into stand-by or hibernate mode.
Wireless adapters are bad about that (grrr D-Link).
Win XP sp2
Dell Dim 2350
I'm having trouble getting my cpu to kick into hibernate mode in a hour either under my login name or the users screen. All the help i can get would be appreciated, thanks.