After drifting from the borg for a while, I began to take up various martial arts over a period of about 5 years. My first experience was with Aikido, Ki society, followed by Tai Kwon Do and finally the one that I am currently pursuing, Wing Chun Kung Fu.
I have found that although some of them do teach philosophies, that they are not actually a religion nor do they divide religious teaching. As Ghost said before me, what is taught is a discipline and a dare I say it gentler way of looking at the world.
Although there are dojos and whatnot that teach and encourage violence or agressive thought processes, the respected ones never do. If you are looking for on for yourself or your children and you are keen for them to have respect and discipline, a simple phone call can help you decide. If they use words like "the best system" or mention "street fighting" then you should probably hang up and try elsewhere.
For children, Tai Kwon Do is good, however you have to watch the high kicks because they have been known to cause back damage. Aikido is an excellent art and very gentle in its philosophy, however to become proficient takes many years longer than most other martial arts. Only Tai Chi takes longer to become a self defence form that I am aware of.
I can honestly say that learning a martial art properly and with the right tutors can only help your self image and improve your life. I have never heard of any detrimental effects from the philosophical views.
BugEye