I firmly believe the squat is the single best weight training exercise you can perform. Involves every major muscle group, increases your energy, and can eliminate back problems if done correctly. I agree, they can be disasterous to your knees and back if done with poor form.

I used to have a lot of lower back problems as a result of a hyperextension injury while swimming in th ocean. Weight training completely cured me. Keep it up, squats are good for you. And enjoy grunting in your yard.