antispyware stuff is a bit like antivirus stuff; if the tools for diagnosis aint installed how do you know if your computer has 'caught a cold'
I do know some folks who run completley unprotected; they rely on a reformat and complete reinstall every four weeks or so to keep them 'in order' ( NOT a practice I would recommend to anyone )
MY advise is to have one installed antivirus program and a healthy selection of other 'nasties catching ' programs
however, it COULD be that you grab a firewall that needs a tweek to enable you to connect to the internet?
also; I hope it goes without saying that common sense and good surfing practices go towards protecting your computer from infections
(sometimes when one reads what folks DO do with their computers one wonders if common sense is