Problem with some malware on my computer

Hi! I badly need some help from you guys! I accidentally downloaded a very bad malware and I was unable to get rid of it. Some applications like Optimizer Pro keeps installing by themselves and it's totally annoying because once they are installed, I will manually uninstall them on the Control Panel and clean my PC with CCleaner and ADWCleaner. After this, everything will be back into normal. But after 3 or 5 minutes or if I restart my computer, same thing will happen again. My dilemma is happening for 3 days now and I really want a quick yet effective solutions for this.
