NTFS partitions have much more functionality and aspects compared to a FAT formatted hard drive. Some of the aspects that NTFS gives that FAT do not contain:

Capability to apply detailed safety to files and folders.
File compression
File encryption
Bigger more proficient hard drive partitions
more safe file sharing
more reliable than FAT
Capability to make use of dynamic disks for performance and fault tolerance

To convert a FAT partition to NTFS, do the following steps:

This conversion is only achievable in Windows 2000/XP/2003. Other Windows editions do not support NTFS.

Go to Start, Programs, and Command Prompt. At command prompt, type CONVERT [driveletter]: /FS: NTFS where driveletter is letter of drive you are converting.

PC will restart and convert.exe will convert partition to NTFS. After you convert to NTFS you can’t return to FAT without formatting drive.

It is suggested that you do a complete backup of data on drive that it is to be converted before converting if anything goes wrong.