If you were to post your personal info on one of these threads, the entire online world can see it, and it's searchable on Google. As far as your privacy settings, no one can see your personal info unless you have provided it on your profile page. Anyone here can visit a person's profile, but if you don't want anyone to see your profile info, you can edit that in your Settings tab. Many people here foolishly give out their phone, email, Skype, Yahoo, etc etc, not realizing how many weirdos are on here, then they get inappropriate pm's or emails, and opine that they shouldn't have given out their info.. :/
I would also suggest for privacy sake, that to protect yourself and your kids, if you have any, that you NOT post personal pictures of yourselves on here. That just gives weirdos something else to inappropriately comment on.