I'm having difficulties with 2 supposed viruses on my computer. Norton anti-virus recognizes they are there but apparently can't delete them. I constantly run a scan but it seems about 20 minutes on my pc then it slows way down. I start to receive norton pop ups saying it identified a spybot worm then deleted it but then 2 more show up. Both of those say norton can detect them but they can not be deleted. Is there another anti-virus better or what should I do at this point?