Obviously the master ball gives you a guaranteed catch, but since you only get one guaranteed master ball, here are some other nominees:
Ultra Ball-Just a Standard good type of pokeball. Always reliable.
Dusk Ball-Worsk great if it's at night, or if you're playing HG/SS, you can get them better since they're in caves (except for Zapdos)
Repeat ball-If you already caught them in a previous version and brought them to your current game, this can work well too.
Quick Ball-Not the best choice, but has good accuracy if you're feeling lucky.