Remove computer adware is the subject I am researching so far. The discussion is wether to use a free software or a cheap/expensive software.

I tend to prefer more the cheap software against the free ones. Well, anything that is free is probably less good than something that you have to pay for. That is my motto.

So amongst all of the anti spyware program to remove adware, I prefer the low cost ones.
Two! 1) An anti spyware adware and 2) An anti virus software

That should be a good choice to protect my PC. I also hyperlinked the favorite software, which I been using for six months now. The other is McAfee which is also a low cost software.

Windows XP users can always make use of the Microsoft Updates, which are very good to keep PC (windows) updated. I also switch on the Firewall from the Control Panel ... and turn auto updates on.

Updated the Browser (IE, Mozilla etc) is also important, for security and stablity...
Not to mention updating the two software, McAfee and No Adware.