Security Tool Virus !

First time ever I got stuck with virus on my laptop,means since I had buy my laptop there was no virus in my laptop till today when I was surfing net with many sites simultaneously and suddenly this deadly virus anyhow has enter my laptop.This virus name is Security Tool Virus! which first I thought was some security software which is scanning my laptop and after scan was over it showed me that there are 48 threats in your computer and I was shocked but I immediately realised that the threats which this software was showing are not real but are safe application software which are installed on my pc.When I close this Security tool software window it again get pop up and ask me to purchase their copy so when I tried to remove it from my pc I came to know there is no option to remove it even from control panel and suddenly my system get crashed.Then I again started my laptop and search for how to remove this Security Tool Software and that time I came to know this is not a security software but it is virus itself.This virus is so deadly that it had block my anti-virus ,notepad and my task manager even when I tried to download any other program to uninstall it,this software restrict download and I get successful in download then it restrict installation of that virus removal software.Still I am confident that I can remove it from my pc but not today but definitely tomorrow or day after tomorrow.Till that I am using Ubantu OS and hope everything will be fix as soon as possible.If anyone want to provide any solution then please leave your comment which will help me and any other who also want to get rid off this Security tool software virus  .