Is a dictatorship better than a weak democracy ?

There's no definitive answer, how good it is depends on your criteria. Dictatorship can be more efficient in getting things done, as was famously said of Mussolini "He made the trains run on time", but it is also more prone to cronyism and corruption. The trouble with a dictatorship, or any other absolute monarchy, is that it is only as good as the person in charge. Democracy at least limits how much damage a bad ruler can do to the country.