Best file format for USB HDD and HOW TO

Hi All,

I want to know what is the best file format to get USB HDD worked with OPTWARE or ENTWARE? How can do this if I am on Windows 8?

I tried Ubuntu 12 under VMWare. Also tried EaseUS for Widnows 8 with no luck as Ubuntu 12 wont give an option of EXT3. EaseUS format to EXT3 but not readable by router.

Best regards,
Webgurru