Different mantras:You can choose one that appeals to you. they are all effective. The Vedas say...There is no need of understanding the language of the mantra, nor is there any need of mental speculation,nor intellectual adjustment for chanting these Vedic mantras. They spring automatically from the spiritual platform and as such anyone can take part in these trancendental sound vibrations without any previous qualificationHarvard University Professor/Medical Doctor Herbert Benson recognizes that meditation on religious words is the most healing of all techniques.