If you can erase that drive, you can reformat it using the "FAT" format type, called "MS-DOS (FAT)" in Disk Utility. Mac OS X can read AND write to that format, and so can Windows. NTFS is read-only for Mac OS X, and I'm not sure about trusting a third-party extension for writing data (even if it worked).
If you only need to use this drive using a Mac (no need for Windows PC access), then you should just erase it so that it gets reformatted using Mac OS Extended (Journaled) as the format type in Disk Utility.