The answer to this question depends on what you mean when you say,
"shutoff". Many of these programs have an option to minimize to the
taskbar, or to run in the background as a process; and this would not
necessarily appear to be running to a casual glance (They would not
show up on the Alt+Tab list, you could access them from the status bar
at the bottom of the screen, etc.).
However, if you mean do these programs run despite being completely
and deliberately turned off - in general, the answer is no. There are
some parts of certain programs (Kazaa specificly, however there are
others) that will run all the time, and these are the advertising
parts (notably Gator).
Limewire has the option to exit, however when you exit it places an
icon in the system tray next to the clock. This program has not
really exited - it is still running in the background, and is still
using resources and bandwidth. If you wish to exit it, right click on
the icon, and click 'exit'.
WinMX also has the option to exit, and will do so. However, if you
click on the 'x' in the upper right corner of the screen, it will not
exit, and will minimise to the system tray. Again, it is still
running in the background, and is still using resources and bandwidth.
Kazaa is very much the same as the previous two, however it has one
major difference. Since it contains 'adware' (Advertising programs
that run alongside the main program), these programs are installed and
run all the time. They will download advertisements, upload viewing
preferences, and randomly pop-up advertisements all the time the
computer is running. Therefore, while the main program may be turned
off, the advertising parts of the program cannot be turned off and
will always be using bandwidth.
To remove the bandwidth-using advertising programs, I would reccomend
first uninstalling kazaa and replacing it with a non-adware supported
program, like WinMX. Then, download AdAware (a very well respected
advertising and spyware removal program) and scan your system for
I hope this helps to explain a little on how these programs work, and
also how to protect yourself from the excess advertising and
unnecessary privacy intrusion that many of these programs undertake.
P2P Background Running
Thanks for the question,