Be blocked by the Police Intelligence Unit Scotland Yard!! Need help!!

I don’t know where to begin. Well, I saw some cute pics the other day. And i thought it might be great to get one as my wallpaper. Download finished and got detected by my installed security tools. Nothing dangerous. But this morning i opened my computer and the warning massage showed up. Shut down, restarted, still the same. Asked me for money to unlock. I m not gonna pay these frauds. I didn’t do anything wrong. What should i do then, guys?

Hi, John Anna! This a knotty one indeed.
It is suggested that you Immediately terminate its processes in the Task Manager.
Then move to Control Panel, when you see any unfamiliar programs on the list, uninstall it by clicking on Add/Uninstalled programs. It is also recommended that you go to Internet Options (click Tools on the opening web browsers and you will find it) and delete all temporary Internet Files and cookies. Launch a full scan with your security tools. You should be able to take control of your machine now. Also, You shall be more careful when browsing online and keep updating all your installed programs. Take care!

Oh, no! How did you catch this thing at the first place? I like to get funny stuff from the Internet, too. I AM SO LUCKY not to get stuck like you. Maybe I should stop doing so. It is not safe out there.