This depends entirely on your teeth condition, your budget, the results you want and the time you are willing to spend for teeth whitening. It also depends on the reason you want to whiten your teeth. If your intention is to make your teeth as stain-free and shiny as possible, then you may want to choose dentist-administered or prescribed teeth whitening methods. These methods might take more time and money, but they're more reliable and effective than most DIY methods.
If your staining is not severe and a more modest (and less expensive) whitening effect is desired, then at-home whitening products are a good solution (depending on your overall oral health). If you want great looking teeth for a special occasion - like a wedding or class reunion - consider a faster method, like laser treatment. Remember, though, a dentist is your very best guide to selecting the proper teeth whitening method for your particular needs.