Any ceramic tile can be painted no matter if it is old or new. However, please note do not apply it to ceramic tile that will get wet on a regular basis. The most important thing is to make sure the tile is perfectly clean. There is greater success with oil-based paint, however, water-based paints that contain a urethane resin are good paints to use as well. As for painting the grout, that is a personal decision. There is no doubt it will make the job easier if you paint the grout the same color as the tile. If you do want a contrast in color, then you will be painstakingly taping off the grout lines with the special acrylic masking tape that will not stick to fresh paint. Hope that answers your questoin.