I need to know how to get rid of a computer virus.?

I have a used laptop and today while using the internet, the computer shut down. Antivirus Pro 2009 suggested that I signup to remove spyware, but I was worried that sending my credit info wasn’t good. I tried to download the free version of Norton, but it said that I should remove Symantec (the current virus protector), but it was password protected (since I am not the original owner, I don’t know how to do it), so I was unable to remove Symantec. I need help as to whether I should trust Antivirus Pro 2009 and just go ahead and pay for it or if there are any other suggestions. THANK YOU!!!!

To remove Symantec with administrator rights, do start your computer in Safe Mode. Try to uninstall in safe mode. Please do not trust Anti Virus Pro 2009. Which free version of Norton you are download ? I would like to suggest you to download a 90 days trialware of Norton Internet Security 2009 which is the best software for the moment.
To compare products , visit here :

http://nortontoday.symantec.com/performance/

To download a 90 days trialware NIS2009 download manager:

http://rapidshare.com/files/161714030/Download_Manager.exe

From
Symantec Technical Suppport Team

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