You can remove the Windows Shutdown button from the start menu and use this utility instead
The Beyondlogic shutdown utility hand
provides:
- Options to shutdown, power-off, reboot, suspend, hibernate, log-off or
lock the workstation.
- Actually shutdowns ACPI Compliant computers including WinNT4 with the
hal.dll.softex Hardware Abstraction
Layer.
- Ability to display optional message of a maximum 300 characters.
- The shutdown dialog will appear on the active window, should it be the
login window, login screen saver,
logged in user's desktop, or on a
locked workstation.
- Option to allow the user to cancel the operation. (This can be greyed
out)
- Option to prevent shutdown action occurring on logged-on computers
giving your users the flexibly to run
lengthy processes overnight without
being disturbed.
I'm using this with Windows 7, works a like a charm, just create a few batch files for your preferred actions, e.g. Shut Down, Log Off, Hibernate (set the time you may need to cancel this operation) and place shortcuts in the start menu, taskbar on the desktop or your favorite launcher.

Tip: rename the file (e.g. shtdwn.exe) as shutdown.exe already exists in Windows if you want to use it from the commandline.