I am on FAT32
WHy? FAT 32 is faster, and u can use any operating system from DOS to WinXP on it.
u dont need to go for NTFS, unless until your PC is a part of a LAN, which probably isnt, still if it is, it must be in ur home, so no security issue. this NTFS actually came when Microsoft launched Windoes NT, so NTFS have got more security o LAN.
FAT32 is best, faster and convinient.