Computer invasion for the experts?

My son was messing on the computer and well we have several of these stupid security softwhere programs on the computer and one which has taken over the screen for some reason i can't delete the programs thay delete then come back on my windows. I have norton security which always works but can't work on this. The main concern is the one on the screen once the computer has loaded its red with a tribal sign say you privacy is n danger download secuity program this is on every users screen will i need some one in to clean the computer or is there anyone who know what to do please no stupid anwsers my computer is a e.system with windows xp

Computer invasion for the experts?house call

Malwares. I recommend you to use two of the following three to scan and clean your computer. Spyware Terminator- http://www.spywareterminator.com/ , Spybot - http://www.spybot.com/en/index.html, or Ad-Aware - http://www.lavasoftusa.com/software/ They are free but reliable malware, spyware and adware removal tools.

Computer invasion for the experts?matchless

Yes, unlike other operating systems, Microsoft Windows is plagued with viruses, adware, spyware and trojans. You've been infected by one of these nasties.

The sure-fire way is a simple format %26 reinstall. It takes just a couple of hours and you're system will be just as new again.