Can anyone explain to me the difference between an HMO PPO and Blue cross?

My job has offered me benefits and I am clueless what is best,They offer 3 medical plans,Blue Cross of Ca.HMO or PPO or Kaiser Permanente.Also 2 dental choices through Guardian and Vision thrrough VSP and Life death dismemerment through Guardian.Is there a website/book for dummies like me.Help I have to fill out the papers and do not want to make mistakes.Anyone with good and bad experiences would be helpful.Thank you!