Computer Security for under $20 a year

I need computer security but I only want to spend around $20 maximum for it and no more. The computer which is suggested please give details if there is anything else extra provided as well. I dont know much about computer security which is why I need advise from forum members.

Why not go for the free security services available?

Just Install AVG Free Version and never download any files, etc from unknown websites.

I was use my old PC for 6 years without any antivirus by using "Read Only Access" method ;P

If you have XP, the best protection is the one that you don't have to worry about--Windows Steadystate. Windows steadystate locks the state of your computer to one you choose. Then, it always boots to exactly the same functioning setup--no virus, no malware, nothing will ever stay on it, even when downloaded. Just one reboot and it's gone.

The other solution is to use either XP embedded to Win 7 embedded. Again, these will only keep what you want in a saved setup and remove everything else with a simple reboot, including bad stuff.

I had to deal with some serious problems with viruses and malware in our business networks. Once I replaced everything with these two solutions, we've not had issues since and no worries about constantly updating stuff.