You could install android onto an SD card but you wouldn't be able to boot a PC from it. Android supports ARM processesors and Windows supports x86 and x64 processors. They aren't interchangeable without an emulator, which you need an OS in first place for. However the new ARM chips being are getting native emulation support for x86 which means you could install windows on an ARM device in the future.
Correct me if I'm wrong.