i guess, i would get rid of windows os-core, replace it with linux/bsd (more likely) and provide a nice skin on top. this would most likely destroy all hopes of having linux / osx having any resonable dominance on the desktop anytime soon. and a unix-y core would be quite welcome among the hackers too. world-domination with a vengeance :o)
edit: one thing that i realized is that _is_ possible to dress unix up quite nicely. an iron fist with a velvet glove.