Math and CS at Vanderbilt and other questions

Is it possible to double major in Math and CS?

How strong is the undergraduate teaching in Math and CS? Big/small classes? TA helpful? Courses taught by professors or instructors?

Is housing guaranteed for four years or upperclassmen need to move out? What is this Greek culture at the school?

Sorry for these many questions. I am sure these might have been asked before. We just have to make a decision soon. Thanks!