LW was downloaded and it slowed down the computer...almost not usable.
Also, LW opens every time Internet Explorer is opened. It seems that it can't completely be disconnected.
What should be done?

It might be a virus. Does it start up by itself after you shut it down? If so, there is a worm that causes that.

Try the fix in this thread: To fix the limewire keeps popping up / no taskmanager bug do the following

More virus info in this thread: WARNING: Viruses on network you should be aware of!

Here are some sites that offer virus help:

http://www.spywarewarrior.com/index.php

http://www.castlecops.com/forums.html

http://forums.spywareinfo.com/index.php?showtopic=79038

You could try uninstalling LW and see how your computer runs without it. Uninstall it by going to C:\Program Files\LimeWire\Uninstall.exe, double click the uninstaller. Don't uninstall using the add/remove programs. See how that goes. If an error message starts popping up then it's probably a virus.

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