You will use your baking dish for casseroles, rolls, chicken breast, cakes, and even Jello. Most kitchens find the 9 by 13 dish to be one of the most versatile.
Skip the cake pan and go for a pretty coated ceramic version that doubles as a casserole pan.
Look for a version that goes from the oven to the freezer, is non-stick, dishwasher friendly, and handles higher heats.
I recommend Rachel Ray Baker. It does all the things AND looks pretty!