A new virus/Trojan encrypts your Minecraft, WoW, and iTune files then tries to ransom them to you. Be careful what you click on. Make sure your anti-virus is updating and actually running, do a scan or at least start one. If it runs, you know it is working.
This is a variant of the better known Crypto Locker ransomware.
Once these things encrypt your files, you are pretty much screwed. You can double down by paying them to release your files. All that does is tell them they have found a rube and empty or overcharge your account. They aren’t going to decrypt your files. All that would do for the bad guys is provide more tracking information for law enforcement. It’s not like they are trying to build repeat business with good customer service…