Answers:
more than potential yeh. a smart scan, is a rushed scan. and a full scan, scan your together comp. but typically, spyware usually is merely within secure places (don't in general stash everywhere), similar to a virus. i tend to run a full scan at tiniest every couple of weeks.
It could. Some malware is designed to secrete contained by computers. A smart scan may lone look at those areas that malware is commonly located and not surrounded by adjectives other areas. Some antispyware and antivirus products recommend that a full scan be done at tiniest once a week save more frequently.
After initial updates other run a full scan .