I started messing around with Linux in '96. I finally made it my full-time desktop in about '99, and switched my wife's workstation over in about 2001. (That took two tries; Linux browsers were still pretty marginal back then).
Since then it's been all 100 percent Linux in our household, including server and firewall. My wife doesn't know what a blue screen looks like (although she manages to find lots of other quirks in the software..)