I am shooting video of high school football. I usually just make an introductory title box, then drag about 150 clips onto the timeline and render. No transitions. Usually it is about 40 minutes of video.

I have found that if I reduce the bit rate to 12000 or 14000 the rendered file is about 4g and will fit on a regular DVD and then will display in HD on an HD TV when played on a PS3 or Blu-ray player.

I have used the HD profiles which produce a m2t file using the mpeg2video codec and have also tried the H.264 profiles which produce a mp4 file using the libx264 codec. In both cases I modified the profile, creating a new one to use the bit rate I wanted. The HD profile is 1920 1080. I am not sure what the H.264 is.

Using the same bit rate, the HD profile creates a slightly larger file than the H.264 profile. But either file fits on a DVD and they both look good playing on the PS3 and HD TV, at least to my untrained eye.

Is there some reason to prefer H.264 over the HD profile or vice versa?

Thanks in advance for any comments.

If you look closely you will absolutely see differences between mpeg2 and h.264.
You should always prefer h.264 over mpeg2 if possible.
But since h.264 is very complex, many players or pcs are not able to play full hd h.264.
If your hardware can play it, then go for h.264.

h.264 is by the way the codec that blue ray disk are using, so any blue ray player should be able to decode it.

Also, MPEG-2 is only good at high bitrates, but H.264 works good at low and high bitrates but at the cost of computational expense as already explained. if you need to go to a lowish bitrate (e.g. < 10000k for HD) to make a smaller file (or streaming), then you will need H.264.