Yes they should! It is all about rehabilitation. It is in our best interest to get them to be productive, reformed members of society.
Prison should be primarily rehabilitative, and secondarily punitive. Otherwise, what is the point. I absolutely hate how the prison system the world over is designed to dehumanize and ruin you. It's wrong. People who do their time, should do so in a way that is to everyone's benefit, and not as an act of retribution or vengeance. We are better than that. Or are we?
I agree completely. Without trying to prepare to reintegrate them in to society properly, all we are doing is letting them sit dormant until they are released and given the opportunity to re-offend. By teaching them to be a good person and giving them a set of skills that would allow the to function as part of a society in a positive way and make the kind of contribution the rest of us good folk do, we are (at least, I like to think) reducing the risk of them re-offending.
Locking them away forever is not an option, we simply don't have the space with the ever-growing number of criminals, so the only logical option is to make sure that when the criminals who have served their time in prison are inevitably released, they are released wanting to be a good person and not wanting to go out and stab the next person they see.