On my first trip to India, I read Dominique Lapierre's book in a single night. I found myself deeply moved by this awful tragedy that could have been avoided if the people in charge at Union Carbide had been more humane. I also recommend you read a few other Indian books and novels before your trip to fully familiarize yourself with the culture and the problems that exist locally.
I wanted to go to Bhopal in order to pay homage to the thousands of victims of the catastrophe, as well as to all those still dying each month from its consequences.
I naively expected to find a city in mourning. But almost thirty years after the event this isn't the case at all. The city is quite a nice place and has a huge souk in which it's very enjoyable to get lost for hours on end. You'll also find a number of very interesting museums in Bhopal.