Sending all SAT scores to universities?

I will be taking the SAT IIs this saturday and I am definitely not ready for them. I am aiming for ivy league, stanford (basically the top unis). Will I have to send all of my SAT scores? If I do very badly on my first SAT IIs (which I know I will) but do really good on my second attempt, will I still have great chances of getting into top unis?

Why are you taking SAT 2s if you are not ready for them? You know that you can take them and cancel them within three business days and then no one (including you) sees the score. Two people have said that Yale and Stanford do not have score choice so you would have to submit all scores but I don’t know about the other schools.