Node is missing from the SYSTEM PATH, try this in your command line
SET PATH=C:\Program Files\Nodejs;%PATH%
and then try running node
To set this system wide you need to set in the system settings – cf – http://banagale.com/changing-your-system-path-in-windows-vista.htm
To be very clean, create a new system variable NODEJS
NODEJS="C:\Program Files\Nodejs"
Then edit the PATH
in system variables and add %NODEJS%
PATH=%NODEJS%;...