They didn't, the first one to come out was Manhunter, which is the movie of Red Dragon, then Silence, then Hannibal, and then they realised that Manhunter was terrible, so they made Red Dragon as a prequel (which also turned out to be pretty crap).
Red Dragon isn't as good as the other two, but certainly not bad. Definitely way better than Manhunter.
Him young was my least favorite of the video series. Red Dragon, although not a great Hannibal movie, was an amazing detective movie, in my opinion.
Do the books show more detail about the psyche of Hannibal?
I never watched Hannibal Rising, but that doesn't surprise me one bit; Anthony Hopkins' amazing acting is what makes Hannibal so great. A Hannibal film without Hopkins is like a Terminator film without Schwarzenegger.