Coffee bar? Keep the coffee and soda in the kitchen and save yourself space and cleaning and grief. Just because you like an idea doesn't mean that it will work in your space. Keep an idea book for the future when you move to another place.

A chalk board? You should post in the Home Decorating Forum and see if those talented people have ideas for you. Post some pictures and see what ideas come up.

Here is a link that might be useful: Home decorating

Post photos of the space, it is hard to make suggestions without seeing the space (and the table/chairs). As for clean up: Put down a washable rug. Pre-treat the carpet under it and around it with a stain preventing carpet cleaner (they make them you just spray on and let dry). Do you really NEED the table and chairs? How many people are in your family? Can you eat at the bar instead? If it's a wood table, you can simply saw it in half and mount the cut side on the wall to make an instant "bar". Chalkboard paint is easy to paint on wood surfaces, just sand it lightly and paint it on.