Hi i had been reading about h.264 for a while it its big selling point was the whole "scalable from 3g to hd" thing. This sounded awesome so i promptly bought quicktime pro. While i love the program, ive got some low res files, and i'm having zero luck "scaling" them to HD. The quality ends up no better than if id just stretched the window, but with an enormous file size. Do they already have to be h.264, or did i misunderstand this whole thing?

you cant INCREASE quality. Tee HD thing is so you can compile your movies that are already high res to HD compatable. If I understand this correctly....