What a strange question?!
I've not considered the OS to have any influence on my Emulator experience.
I'm a Windows XP Pro 32-bit user (isn't everyone?) but Win98 was just as much fun. Cept crashes were a bit more fatal back then
I tried Vista Ultimate Edition when it came out but it was considerably slower on the same hardware as XP and offered no enhancements on the user experience (for the hardware I had) so I reverted back to XP