Thanks for your reply Stan. Yes unfortunately i could not solve the Encore problem after a frustrating day of trying so many different bit rates, formats and field orders. It seemed like I did everything I could think of to try rectify the issue but with no success, the footage was still jumpy.
The field status was progressive, the information from mediainfo didn't give me what order whether upper or lower first so I tried both on a section of the footage.
I'm completly stuck as to what went wrong but it seems to be working fine in DVD Studio Pro. Thanks for your help.