My sister is exactly like this. I told her that my laptop is 10x faster than her old Mac after she started talking stuff about me using my Windows laptop. She said basically what your Dad said, and then her shiny Mac turned into a paperweight after she opened like 30 "Finder" windows of the same thing, trying to prove that it was better.
Lappy = Windows 7, 4GB ram, 256GB HDD (About), some GPU that I can't be bothered to think of.
Mac = Mac OS X 10.4.11, 1GB ram, 120 GB HDD, some old ATI GPU from like late 2004 or early 2005.