How do i clear my Labtop?

I have all these viruses like tojan horse and worm on my labtop. i do not want to buy antispyware and i have no idea what to do. i have windows XP and i have like five viruses out of nowhere. it says i have spyware, and all these annoyign pop up keep coming up. i need help on what to do or how to just clear everything on my pabtop, and start from a clear slate. how do i get rid of viruses and how do i clear my computer of memory,history, and viruses?

How do i clear my Labtop?abtuvurys 2005

I recommend downloading Spyware Doctor Starter Edition (part of the google pack)

Free AntiVrius

- Grisoft Avg (2nd Best)(most popular)

- Avast

- Avira AntiVir (Best)

- PCTools Anti-Virus

Free AntiSpyware

- Spyware Doctor Starter Edition (The Best)

- SuperAntispyware (2nd Best)

- Adaware 2007 (most popular)

- Microsoft Defender

- AVG AntiSpyware

- Spyware Terminator 2

- Spy Hunter 3

- Spybot Search and Destroy

More Antivirus and Antispyware Information and links to the software vendors are found here http://pcsafety.info

How do i clear my Labtop?antivirus programs

There are free antivirus software out there, but if you've had this for a while, it may have downloaded a lot of other virus's. I've dealt with a virus like this before (Trojan.Zlob) and it took too many manhours to totally get rid of it. It would be be better if you just backed up your documents and reinstalled windows from your windows cd.
lol...people on this site will have ur comp so full of antimalware prog's u wont know what 2 do w/ them or how 2 use them.....talk about overwhelming u....this is what i would do