It Wont Work - Its already been tried
Jeff, et el.
IBM tried about 3 years back to wrestle windows mainstream applications over to OS/2 by cleverly installing the WIN API into the OS/2 kernel.
Guess What - didn't make one ounce of difference. Having been a highly paid OS/2 consultant in the past working for BIG corporate names, I can tell you that what you propose wont work.
Firstly - Any platform that is put on Linux to support windows apps will be a VERY HARD proposition. IBM conceeded that their effort was as good as anyone outside MS could do - given that MS does hide some of the API's that their applications call ... possible to get eventually find a workaround but very difficult.
Secondly - You really have to look at the corporate incentive to switch to a different OS. What do they really get switching to a new OS ? the support nightware and cost$$ of ensuring Windows based apps run on this non-native OS will be high.... does this outweigh the fact that Linux is free and Windows costs $50/seat ?? probably not. Its direct Vs indirect costs.
Hey ... I'm as bitter as everyone else here .. why do you think I'm hanging around the Linux world these days ? OS/2 has been given the death knell by IBM in 2006. Linux has to stand on its own merits of which it has many.