You can learn to hack just fine on a widows system although i would suggest 2k.
Ummm ... if we take "hack" to mean kluge and/or take stuff apart to figure out how it works, then I'm not sure this is a great idea. NT makes it awkward to hack around in the kernel, as (among other things) they've masked the parallel port address. So you can't do bit-manipulation on the parallel port. Which takes away from low-level driver stuff.

Now - seeing as how 2K followed NT's track, I'd imagine that the same holds true for 2K, though I've not used it as a robotics platform yet.

Anyway - just something to keep in the back of your mind if you're looking at doing low-level code on windows. 95/98 is what we used for our VC++ (not our paradigm choice, BTW) robot control via the parallel port.

~N~