I have a network of 4 computers. Opensuse and Zorin Os configured as Samba file/print servers. And two Windows 7 Home Premium computers setup as client computers...
AFAIK, there is no way to defrag NTFS from an non-Windows OS. So if you still want it defragged, you have the answer. If you don't need NTFS for portability reasons, then reformat it for a *nix filesystem