Dynarec is for Dynamic recompiler, most emulators got that, it's a faster "optimized" way to emulate stuff ( as I know), but sometime can be more buggy .
and about the things you wrote first, I think it's about pkmn Colloseum *sigh*.
It's just the options to set in dolphin, under the emulation menu. and for the renaming, you use GC-Tool , open the iso and rename the movie folder...