Craig has a ton of adware on his PC from installing software. Leo can't stress enough how important it is to be careful where he gets software. Since he doesn't really know what he has, he could have opened himself up to far more bad things. Leo suggests turning off all extensions, deleting them from his extensions folder, and running as a limited user. Look in "add/remove programs" for entries he doesn't recognize and remove them.
Joe's computer is slowing down and he'd like to buy HP's speed up program. Leo says that Joe needs to be sure he's getting it from HP and not a third party because it could be malware. Leo says even a utility from HP is just a way to sell him something he doesn't need. The best thing to do is just do an annual format and reinstall. It will refresh the drive and get rid of all the "cruft" or bit rot that builds up over time. So John should backup his data, format the hard drive, reinstall Windows, and update it completely.