LOL didnt finish Zero's mission and beeing all the way over there? How is that possibel? if you want somoene to do Zero's mission, ill be pleased to do so, but i geus you should just make a new topic (you ask for more missions at once)
Well, Zero's missions aren't needed to finish off the storyline missions, since they're only needed for 100% completion, but I only suggest this to the players so they won't have and mission markers at the end of the game, and have the pleasure to enjoy every single mission of San Andreas. Take a look at the Mission Tree to see which missions are required for finishing the storyline and which aren't.
Like miromiro, said you don't need to complete the Zero's missions if you need to complete the storyline. Most of Zero's missions are annoying but once you have done them you will feel a lot happy and glad.