Around 2-3 days ago I was on my brother's laptop, and as I was surfing the internet I noticed alot more ads popped up than usual. I just shrugged it off and continued surfing. Then, the next day I turned on the laptop to see a "Windows 7 Recovery" window saying I had "critical" problems with RAM, memory..etc. I became suspicious as there were many telltale signs of a virus. I looked the problem up, and saw that my hunch was right. Then I wondered, how come this virus wasn't removed? I then just remembered that my dad had forgot to install the Norton Internet Security 2011 on the laptop when our old subscription expired. So, I re-installed it (?) and think that Norton would take care of everything. But, it seems that it isn't detecting it. I can end the windows 7 recovery program by using Task Manager, but it somehow restarts itself around 5 minutes later. It's process in the task manager is sevel numbers and letters followed by .exe. I have no idea what to do, can somebody help me?
P.S. Also, when I looked up the problem, there were various solutions but many involved downloading other suspicious anti-virus programs and editing the PC's registry. Please help!