Virus, malware, and Windows 8 [View all]

Just did a security scan on the hard drive. It only took 29 hours since apparently there are over 1.2 million files on the drive. Is there a "classic" folder where virus and malware tend to hide themselves so I don't always have to scan the entire drive? Oh, and in the pre-Windows days there used to be software that would clean ones drives of obsolete and redundant files. Do they still exist?