Help me, I am unsure who to vote for.?

This is the first year that I am old enough to vote. My parents say it doesn't make any difference who we vote for they think that Washington will get who they want in the office. My Grandmother says I should vote, but even she is becoming discouraged. My family mostly vote Democrat but they say to decide for myself. I don't like McCain and I am afraid for Obama. (to many bigots out there)