How to protect my computer?

I purchased a computer a few months ago and I don't have any software installed for security, I don't know much about all that security software, I installed the Windows live one Care but it expired, What software do you recommend to protect my computer from viruses and spyware and what ever necessary, I don't care if I have to purchase just please explain what to protect my computer from and what software is the best.

How to protect my computer?anti virus

I have used AVG Anti Virus, Zone Alarm Firewall, Spy-bot Search and Destroy and Ad Aware both spyware killers for years. They are all free for personal use and I have had no trouble with Viruses Trojans etc. AVG does not slow the system down as much as some other products and Zone Alarm allows a lot of personal configuration unlike the Windows Firewall. They can all be downloaded from the following linkhttp://www.computeractive.co.uk/. On the home page select downloads and then the appropriate category.I also use Windows Defender from the Microsoft site. It is safe to use two anti-spy products but never use more than one A/V as it can cause conflicts. You should run A/V and anti spy weekly. Hope this helps

How to protect my computer?auto protect

One of the best free antivirus software is by Avira called Antivir. Get Spybot Search and Destroy. Also get Comodo personal firewall.

All of these should be able to adequately protect your computer for free. Just google their names to get to each of their websites.
The first answerer is right. Avira Antivirus Personal Edition Classic is a very good, free antivirus software. Just keep your Windows firewall on and install Avira Antivirus Personal Edition Classic as well as two free antispyware programs. Antispyware is different from antivirus as it protects you from threats that operate differently than viruses. Ad-Aware 2007 and Spybot Search %26 Destroy used together should be good enough. That's all you should need: One free antivirus program, the Windows firewall, and two free antispyware programs.