I visited ooty last month. There was a flower show during that time. It will be painful to go to ooty during any festive season bcs the traffic on the hilly road is very high. You may suffer hours on the way. And hotel accommodation may difficult to find. So plan it on normal days. If you are expecting some advantures kind of places there then you are wrong. You can enoy the lovely flower gardens and boating there. I would recommend if you go, go with proper planning and adequate information. Thanks