I have AVG and Spybot on my computer... I use spybot for spyware when it gets on my pc and AVG is probally the best Free Antivirus out there... Also just to let you know if you go to My Computer < Tools<Folder Options<View<Hidden Files and Folder<Click on view hidden files and folders.. It helped me find spyware and trojans that were installed on my computer and then hidden... It may help you... IDK??
AVG is the way to go. If you cannot get rid of all your problems, back up anything important, format your computer. After formatting, download the following free software:
If you do install all at once somehow it will be worse than troyan
Installed kav+panda titanium + nav ... they tried to delete eachother , and then they deleted half of my system 32 files resulting that windows weren't even loading after that lolz