I have a virus problem an somebody help me?

i am 13 years old and my father is a verybad man and i dont have any money to pay an antivirus program . I need a free full antivirus or antispyware because i am infested with the Trojan virus i scanned the computer with the NOD32,Adware-SE and Spyware Blaster but no succes.When i start the windos explorer i dont see my default page, i see a website safety security or something like that and he told me that i have a virus and i have files exposed on the internet such as System32,Program files and other files.They said that i need some update or patch but it doesnt work yesterday i tried to download the update but it says that Page cannot be displayed. what should i do i need to get this virus out of my computer but how?

I have a virus problem an somebody help me?live update

First of all, one of the easiest wey to stop online attacks is, STOP USING INTERNET EXPLORER. Ever noticed that add ons can be attached to that particular browser only. As well it uses ActiveX controls, whether you need it not. which allows your computer to be identified. Both Netscape and the latest versin of Firefox gives you the option to use ActiveX when it's actually needed.

Secondly, I would not recommend AVG to anyone. It's crappy and useless. Iknow from having to deal with repairs on infected systems that ran AVG. I would recommend AntiVir Personal edition, whic 100% free, updates and all. http://www.free-av.com.