As you currently do not have any virus protection on your computer my advice is to reformat. What you are going to want to do is back up all of your old files onto a separate drive. External disks are relatively cheap these days. Then follow the instructions that should have come with your computer in regards to reformatting. Don't forget to export your bookmarks from whatever browser you are currently using. It will come out as a text file but can be imported after reformat. Once you have reformatted get AVG antivirus. It's free and it works, in my opinion, better than Norton or Mcaffee. Link
AVG Free Advisor - Free antivirus and anti-spyware downloads Next you want to get Firefox instead of explorer for your web browser. I find it to be safer and more secure. Link
Firefox web browser | Faster, more secure, & customizable There are several security add ons that you can choose. I uses 'no script' and manually allow sites that I like. Next get Adaware from LAVASOFT do NOT fall for any product that calls iteself adaware unless the url is lavasoft. Link
Ad-Aware @ Lavasoft - The Original Anti-Spyware Company - Lavasoft Run it weekly to be sure you don't have any crap that Firefox didn't catch lurking in the bowels of your computer. Be careful what you allow it to delete though because sometimes Windows updates look suspicious to it. When in doubt don't delete. Next get Spybot. Link
The home of Spybot-S&D! Same thing as Ad aware but it can find some things that Ad Aware doesn't. Once again run it manually once a week. You probably got those viruses etc from file sharing (*coughdownloadingporncough*) when you do that you open your computer up to anything any pimply faced geek can come up with so be sure to scan any file you download before you open it. If you visit Myspace often be aware that all the little script kiddies have pages there too and they just LOOOOOVE infecting computers with whatever crap they can dream up. Lastly, and this is very important, I want you to take out a notebook and write 'I will not use a computer without virus protection' 100 times with a number 2 pencil. Seriously now... what WERE you thinking? By the way here's a description of your virus. You need to get cracking on getting rid of it. Discovered: April 27, 2005 Updated: February 13, 2007 12:38:04 PM Also Known As: Win32.Mytob.DG [Computer Assoc, Win32.Netsky.AH [Computer Asso, Email-Worm.Win32.Mydoom.am [Ka, W32/Netsky.b@MM [McAfee], W32/Mytob-CI [Sophos], W32/Netsky-B [Sophos], WORM_MYTOB.EK [Trend Micro], WORM_NETSKY.B [Trend Micro] Type: Worm Systems Affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP W32.Netsky.AI@mm is a mass-mailing worm that uses its own SMTP engine to send itself to email addresses it gathers from certain files on the compromised computer, and copies itself to mapped network drives. The worm also downloads a copy of Backdoor.Nemog.D. Protection * Initial Rapid Release version April 28, 2005 * Latest Rapid Release version April 28, 2005 * Initial Daily Certified version April 28, 2005 * Latest Daily Certified version April 28, 2005 * Initial Weekly Certified release date May 4, 2005 Click here for a more detailed description of Rapid Release and Daily Certified virus definitions. Threat Assessment Wild * Wild Level: Low * Number of Infections: 0 - 49 * Number of Sites: 0 - 2 * Geographical Distribution: Low * Threat Containment: Easy * Removal: Moderate Damage * Damage Level: Medium Distribution * Distribution Level: High Writeup By: Yana Liu The Trunkmonkey Technical Support Edition Now available exclusively at Specktra.net