Computer Shutdown

How long should it take a computer to shut down?
Mine take 4 mins to log off after that it will take additional 4-5 minutes to shutdown,is anythingwrong with my system?

Its depends upon your system speed and installed s/w and current running process in your system,You can easily know this by checking the task manager.
The computer is marking all of your work and shutting down all of your applications. it should also take your computer a long time to boot up as well.
alter your start up applications. The little light that indicates your hard drive is still running is the prove to the length of your shut down time. If you are using a lap top NEVER try to shut it down in a hurry, it will just make things worse next time you start the System.

The speed of shutting down the pc depends on how many software is already working in ur background coz the windows need to close all the processes before it shutdown itself.
Usually log off is something different than a shut down as in log off all the system files are already loaded only personal settings are changed during log off. Shut down depends upon how many software u have loaded or is there any updation pending.If during shut down you get any message like END NOW an appliction then its problem otherwise its normal. or you can repair your windows if still you have any doubt in your mind.

If an update is pending ,the system will take far longer time to shutdown.