XP is able to read/write in both NTFS/Fat32 quite nicely ! The one benefit though with NTFS is that it's a MUCH MORE stable system for files !! I've lost power once or twice during storms and this baby is still ticking away without data loss !! So if you gonna have other partitions other than C: drive....say D and E, you should be fine with Win 9x seeing them just fine, but if you have XP as NTFS....Win 9x won't see it at all. Good luck ! You also may want to look into Partition Magic 7....one of the best partition managers out there for adjusting both NTFS and Fat32 partitions. Though XP does have a nicer disk manager than 9x....no where near as nice as PM 7.