What are the best codecs and formats for importing video?

I've been trying to figure t$$anonymous$$s out for months now, and there seems to be very little helpful information out there!

I know that Unity supports the same formats as Quicktime (w$$anonymous$$ch needs to be installed) and that Unity automatically converts video files to Ogg Theora,but the only format ive been able to successfully imort to unity was a .mpg file using the "MPEG-4 video (mp4v)" codec.

All of the other file formats I've tried have failed, even the other .mpg files!

Adobe After Effects will only render t$$anonymous$$s format out as $$anonymous$$gh as 720x576, as far as I can gather.

How do I get HD video into unity???? (I'm using v4.6.1)

p.s. I have also tried pre-formatting my files to ogg theora using other software with no success!