i have no idea how people get so "easy" infected.....my self i do not use a antivirus for more that 7 years, the only time i do have a bad infection have be with sality that corrupt my all exe files and have be by my own mistake ....
How to clean a pc for free without to much around and a few time, my first choice if the infection is bad is use COMBOFIX is free and can be found here
http://www.bleepingcomputer.com/download/combofix/ , now, i have no true info if is working on windows 8.1 and 10 i have not use it in any of this OS i cant give my experience, on the page say will not run if the data is up to date then you should not use it in any of this OS.
this program is easy to use and will remove basic everything that is around in the pc that should be not, in case that the doubts are to much and bla bla just visit BLEEPINGCOMPUTER website go to the forum create a username go to the logs zone and read what do do
http://www.bleepingcomputer.com/forums/f/103/am-i-infected-what-do-i-do/ is free they will help you for free and will not take the all life.
if you believe you can handle then run combofix and follow the steps, be sure create a restore point before start wherever combofix do a restore point before start.
In any case for the ones more afraid of use combofix i recommend use AdwCleaner, this tool is very easy to use and is free,
http://www.bleepingcomputer.com/download/adwcleaner/ , download it, open, scan the pc and when finish yeah press to get ride of all garbage, a reboot will be need so be sure you save the all stuff before u do it.
In case the problem is not solved you already know get combofix and go for it, if not them go to the forum i have already talk and ask help !!
If the virus is a piss of crap bad guy with big bloody eyes and is not even allow you enter in the OS what to do ? Simple, reboot the pc and chose SAFE MODE, every brand have is own key F8 F11 F12 and go on god knows what more, so check it what is the key for safe mode and use it!
What to after enter on safe mode, lets see, if the bad guy with bloody eyes is run on start up that means he have a entry on the start up menu , so we go to the start up menu and we find the dam ugly monster entry and we disable it, you have doubts what keys is ? no problem even that you disable almost all nothing bad gonna happen to the pc , after disable the wannabe entry of the virus reboot the pc enter on normal mode and clean it up with the tools already provide or you antivirus, well your antivirus is sleeping that is why he eat the bad ugly monster, so you better stop in give them money for do nothing more that jump in fake alarms.
how to use combofix ????? there we go
http://www.bleepingcomputer.com/combofix/ how to use AdwCleaner is to dam easy to use lol but the info is on the same page of downlaod.
Good lucky in clean the pcs for the dam virus monsters lol !!!