According to some tests, Apple Prores outperforms PhotoJPG, but it is bigger in filesize (2x as big at least).
I don’t think there’s an ecoder for windows though, only a decoder.
To encode to PhotoJPG you could check ‘Mpeg Streamclip’. It’s a great app for converting, free and handy for those tacky .vob files and whatnot as well.
You can find it here : http://www.squared5.com/