Good antivirus. Don't download random emails with "unknow" attachment
Is it true that this virus is spread via email, what about security like yahoo and google? I am so scared .. 
Install Linux and dual boot it with windows. I use Linux when I am browsing and checking emails since viruses barely work in linux!
I heard that Linux is not affected by virus. But my problem is I don't know how to use Linux because it is too complicated to install and used. Do you have some guides?