I would agree with the above, do a little google digging and you will have most of your answers. I will provide some quick thoughts to help you on your way.
1. Which among the top 50 schools have class size of less than 200?
THERE SHOULD BE A FEW, BUT YOUR BEST BET IS TO CREATE AN INITIAL LIST THEN SEGMENT YOUR LIST BASED ON THIS. I KNOW WISCONSIN IS A SCHOOL THAT HAS LESS THAN 200 STUDENTS PER CLASS
2. Is there a separate ranking of 1 year MBA programs? I have observed most of the rankings consider both 1 year and 2 programs during evaluation.
THERE ARE ONLY A FEW IYR PROGRAMS, MOST PROMINENTLY INCLUDING KELLOGG, CORNELL, AND INSEAD BUT IN EUROPE THE ONE YR MBA IS MORE COMMON
3. Which of the american schools have top rated 1 year MBA programs?
KELLOGG AND CORNERLL
4. Is it true that some top ivy league MBA programs are skewed more towards Finance & have better industry connect with the financial sector?
YES, HONESTLY MOST OF THEM DO SO I WOULD NOT NECESSARILY USE THIS AS THE LITMUS TEST FOR YOUR FIT. DO SOME RESEARCH AND DIVE A BIT DEEPER HERE
MOST OF THIS INFO IS EASILY FOUND, I'M ASSUMING YOU ARE EARLY IN YOUR RESEARCH PHASE SO JUST DOUBLE DOWN SPEND SOME TIME AND YOU WILL HAVE ALL THE INFO YOU NEED