If you want to convert your hard disk partition to NTFS, do as follows:

1) Go to “Start–>Run” and a command prompt will open up.
2) In this command prompt, type “CONVERT [drive letter]: /FS:NTFS”.
3) After doing this, Convert.exe will attempt to convert the drive for you.

If you want increased security and faster data encryption, go ahead and convert to NTFS. If you want to run multiple Operating Systems on the same partition, FAT is the way to go. Note that converting to NTFS may cause loss of some files, so make sure to back up what you absolutely need.