Can anyone advise on the best encoding settings please?

I need to encode my edited footage down to around 15-20MB per min while retaining the best possible quality and 640x512 size or original size.

I've made a 1min clip to test diffent codecs out but I can't seem to find the correct settings I have also tried TMPGEnc.

Any help would be appreciated.

My edited footage is DV PAL 25fps @ 720x576 interlaced. The final Clip will be for the web.