Should I switch to Ubuntu or stay with Windows 7?

I have been using Ubuntu on my computer for about a month as a Live user and I haven't used Windows ever since I started with Ubuntu. I really want to overwrite my Windows and install Ubuntu on my HDD, but I'm afraid that when I do, I'll need something that only works on Windows. If I get on my dad's computer, then he'll laugh at me and rub it in that he told me that I shouldn't have installed Linux. Should I stick with Windows or install Ubuntu?