I have a betta and 2 cories in a 5 gal. and the betta loves to chase them around. he'll even hide in stealth mode. he loves to chase but has never "attacked" them.
as for feeding, my betta will eat the hikari sinking wafers that i feed the cories. he doesn't like flake food so i throw in a few flakes near the filter flow which will eventually make it down to the bottom of the tank for the cories.
so far, everyone seems pretty happy and they've been living together for about 3 months now.