a little history, not too much tho, you would get bored stiff.
the first computer i ever used was a Apple ][, i loved the stickey bears series, q*bert, and other memerable educational titles, that math one was fun, cant remember the name. the text based RPGs were great, and the ASCII games were a lot of fun back then.
the first mac i ever got addicted to was an Apple II GS, it was an apple ][ that looked like the mac. the first mac i ever had as my own was a 6400/200 circa 1997 when i graduated high school, it was a gift from my aunt. i maxed the RAM and the cache in that thing, also put in a faster video card, and it now runs Yellow Dog Linux, tho thats not the first distro it has run.
the last mac i ever owned was a PowerBook G4 500 circa 2001. i have had Yellow Dog on my TiBook, but now run OS 9 on one partition and OS X on the other.
in between the Apple ][ and the TiBook i haved used many macs, pretty much every model at some point or another. i have used DOS, Windows 3.1, 95 - XP, NT 3.5, 4, 2k - just not on a day to day basis. either at a friends rig, or a server at work i maintained, or a workstation at work i helped teach people how to use.
i have used SGI IRIX, Apple A/UX, a few versions of the Amiga OS, and many distros of Linux. i am eager to really use XP tho, as it is the most advanced version (like Mac OS X) of the OS.
i have gotten a lot of flak from friends about getting a windows box. i could care less what they think.