Ouch... sorry to hear that.
Is this because of an injury?
Well I would try either hack squats, because you have some back support and you said that reg. squats hurt your back, or leg press. Both are compound movements that you can go heavy on.
If this isn't from an injury:
I would try doing them and working on form, maybe get a belt if you don't have one already. and maybe work on two or three sets as a warmup to doing hack squats or leg press. and on workout 2 just try doing them slow and really utilize the amount of Time Under Tention.
I use to never do squats also and always gravitated to hack squats because of a back injury. but ever since a friend of mine convinced me to start out slow and really work on form and your core muscles for stabilization. I've grown to love them and they are my favorite exercise.