The performance will be identical. NTFS on GPT will be the same as NTFS on MBR.
File System do have effects on performance, Phoronix usually do Reviews of that. There are way too many variables, and usually a File System shines in something but is average in other areas. This obviously has no impact for Windows users, whose only realistic choice is NTFS in regular HDs. And no, FAT32 is horrible, not exactly in performance in which it may be superior to NTFS in a variety of use cases, but in overall reliability and features.
Can't say. Newest Microsoft OS I ever used was WXP. I have spend tons of time to confine them to the realm of Virtual Machines.Can you even install anything newer then XP on a FAT32 partition? I must admit I haven't tried... :hmm:
Not that I'd use FAT(32) for anything other then external media.