HELP me get rid of BACKWEB SECURITY NOTICE???!!!............?

I have this notice on forefront of screen for weeks...tried numerous anti-spyware/anti-virus etc...see list! I've also learned that it may be more harmful to outright remove it from computer! I don't even know where to start that process anyway (first touched a computer 9mos ago!) I have a HP Compaq with Windows XP which I bought almost a year ago. Does anyone have any other advice or solutions?---will need easy to follow /specific instructions ...Spybots search and Destroy http://www.download.com/3000-8022-101221...

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HELP me get rid of BACKWEB SECURITY NOTICE???!!!............?malware