Sorry for the confusion. It's a messy situation with all the "standards" out there, and it doesn't help that MPEG-4 encompasses containers, audio codecs, (multiple) video codecs, pictures, fonts, and more.

Blu-ray movies are also complicated, as there are 3 different video codecs supported. The older MPEG-2 video formats DVD also supported, the newer H.264 AVC format, and Microsoft's VC1 format. Your workflow may work with some of these, but keep this in mind if a particular disc is giving you problems. Most now seem to be H.264, but older discs may use the others.

Windows 7 without any codec packs should just work with an H.264 video inside an MP4 file container. Shark007 is likely adding support for MKV containers.