Can you change from run flat tires to nomal tires on your mini cooper?

Yes you can, although its best that you take it to a dealer or specialist in MINI's to ensure the existing RFT warning system does not have problems. You should not have problems, but with most things, there's no guaranties. You'll definitely enjoy a better ride and better longevity on a new set of tires. You'll also need to get a 'donut' spare tire, just in case you have a flat.