As ajones said, your betta will love the bloodworms and brine shrimp, but unfortunately those are supposed to be their occasional indulgences rather than the main course.
I also heard that you're supposed to drench live foods in garlic juice to kill microorganisms before serving to your bettas.
Currently I'm feeding my guys New Life Spectrum (Betta formula):
Most of them get two pellets twice per day, and one of them gets small pinches of the NLS Growth formula four times a day. Sometimes I soak the pellets in garlic juice because the garlic's good for their immune systems. The only drawback is that the pellets sink easily when soaked in garlic...but the fish are little piggies who chase the sinking pellets and snap 'em up.
Hikari Bio-Gold is also pretty good. I once had a betta to whom I only gave two Hikari pellets once a day (I was misinformed... two is too few) and he somehow got really huge within three months of having him.
But anyway, I decided to give New Life Spectrum a go because it's organic.