Easiest component will be a triac or SSR but they have a bit of leakage. As for the zero crossing / micro, it's best to use a small SMPS / transformer and use it to power a zero crossing detector + an opto coupler. The MCU can drive the opto, turning it on, which combine with the zero crossing detector, turns on the triac. There's actually a post regarding a low power zero crossing detector on the first page of the forum if you scroll down a bit.