Here's one nifty trick. Apple iOS encodes to .m4v are actually .mp4 not .mov. You can change an .m4v to .mp4 by hand and they will work in WMP12 (Windows 7). They won't play in WMP11 though but will play in Quicktime and VLC though.
In Quicktime Pro you can also create H.264 .mp4 but other than .m4v, I don't think you can create H.264 mp4 in Compressor. Compressor's .mp4 is the older MPEG4 Part 2 (aka Quicktime 6 compatible).