New Protect

Why my computer can not run? Before is no any problem there?
Sometimes our computer ever got problem. From electric is not stable until broken by virus in our program. Part of we already have some protector for cleaning our computer from some virus. What is new one virus protected was created?
We just want to know "what is and where is virus protected program can I get?". If part of you know that, just send me a message by comment. Thank you for your attention and help. If any free virus protected I'm very interesting...hehe...thanks for all your honest.