Spyware has become a major player in compromising computers, and the situation is not going to get better any time soon. It can introduce viruses, trojans and worms, and attempt to send out information about you. It is the unwelcome guest and needs to be removed. 

The worst of it is that you probably downloaded the spyware, albeit inadvertently..

Some basic steps to removing Spyware/Adware..

First step is to run a one shot virus remover.. I have found that Trend Housecall works for people.. download and run it..

http://housecall.trendmicro.com/

.. select the 'online scan' and follow the directions given.

This takes a while to complete but is a necessary first step.

You will also need to download Spyware removal software.. Spybot and Adaware are available at these websites.. both are free.. download and run them.. don't forget to check for updates after you have started them..

Adaware SE -  http://www.lavasoftusa.com/software/adaware/

.. And how to use it

http://www.bleepingcomputer.com/tutorials/tutorial48.html

Spybot S&D -   http://www.safer-networking.org/

.. And how to use it

http://www.bleepingcomputer.com/tutorials/tutorial43.html

SpywareBlaster - http://www.javacoolsoftware.com/spywareblaster.html

.. And how to use it..

http://www.bleepingcomputer.com/tutorials/tutorial49.html

NOTE.. FOR Windows 2000/XP users ONLY. Ewido online scan - http://www.ewido.net/en/ .. 

The full installable program has been replaced by AVG Anti-Spyware 7.5 since the takeover by Grisoft

CWShredder will eliminate CoolWebSearch and variants.. there is a free download here..

CWShredder.. http://www.intermute.com/spysubtract/cwshredder_download.html

To use CWShredder, simply start the program, use 'check for update' to make sure you have the latest version, then hit 'fix.' It will check your system against a list of current CWS variants, and fix any infections it finds.

You must also run a firewall and anti-virus program.. here are some links for you..

Zonealarm Firewall (free)..http://www.zonealarm.com .. recommended

AVG Anti-virus (free).. http://free.grisoft.com/freeweb.php/doc/2/ .. recommended

The weekly 'housekeeping' will not take long.. run Adaware, Spybot, and SpywareBlaster weekly, ensuring that you update them prior to starting a scan.