My mum and dad had both being using Macs for different reasons since the late '80s, so a Mac was the norm to me.
When I started high school and wanted a computer of my own, all I needed was Office, so I got the cheapest PC available at the time (was about £400. 300Mhz, 16MB RAM, 4GB HDD....). Then a few years later it was proposed that I could a) go to Florida for 2 weeks or b) have a £600 PC. I chose the PC. Then when I left high school and started college, I didn't just need Office anymore; I needed DreamWeaver, Photoshop, InDesign, Flash, and Final Cut would be very handy too. Luckily my dad had just updated to a new Mac, and the new versions of all those programs (minus FC), so I got his old machine with everything on that I needed.