Answers:
Your computer is never safe and sound. It's purely a bit cleaner. Don't be surprised if you run another antispyware and you find more staff.
There are a few moral practices to dull the risk of spyware and virus. Some of them are particularly popular. Some are not so specified.
Yes and no. Some spyware can stow form secure programs or the program might not be 100% up to date you did not specify that. Also spyware is not the with the sole purpose threat a computer can enjoy and unless you try to prevent yourself from getting more spyware your never fully past the worst.
maybe run the scan a few times to get sure..
Spyware on a Mac huh? Unless somebody have access to your Mac to install spyware it's most imagined a Macscan FUD. Download and install this instead
http://www.obdev.at/products/littlesnitc...