You want an Intermediate codec, not a delivery codec. Intermediate codecs are high-quality (to prevent loss) but are not necessarily playable in real-time, due to their size. Delivery codecs are lower-quality, but playable.
Delivery codecs are Sorenson, H.264, and MPEG-2. The latter can also be an acquisition codec (HDV), but it’s a compromise.
Intermediate codecs are Animation, Photo-JPEG, TGA sequences and so on.
Animation is higher-quality, but larger file size when compared to Photo-JPEG at about 90% quality. PJPEG is often quite acceptable, since stock houses use it. If you have the space, use Animation, if not, use PJPEG. Hey, do a side-by-sdie test to see if you can see the difference. Then re-render those clips 2-3 times and see the difference. It’s really up to you.
In other words, don’t use H.264 as an intermediate codec. Only use it for the final render.
Now if you’re going to DVD, use Animation, then compress (as required) to MPEG-2 — that’s your final delivery codec. Use Compressor, Squeeze or Encore to compress to MPEG-2.
Does that make sense?