The best part of this movie is certainly the visuals. I think all the CGI giants are done really well as well as the beanstalk and amazing scenery. I don't know if I would say it is quite to the level of Snow White and the Huntsman in terms of the visuals, but it is pretty good. Like I said, there are many complaining that the story is too boring and while I disagree with that, I can maybe understand where they are coming from if they were perhaps expecting something totally different and groundbreaking from this, I don't understand the complaints about the characters being bad. I thought all the characters were fantastic and the acting was superb. Specifically this movie stars Nicholas Hoult, who is fresh off his great role as R in Warm Bodies, playing Jack. And although being Jack is much different than being a zombie turning into a human, he does a great job in this just as he did in Warm Bodies. Eleanor Tomlinson isn't a name I have heard very much, but she plays the princess and although you can say her role is very cliche, I actually think it works quite well because the chemistry between her and Nicholas Hoult is very strong. Also you have Ewan McGregor making an appearance in a big name movie for the first time in a while and he is great as always. We also have Ian McShane, Stanley Tucci, and several others who do a good job to make this work.
Overall, I wouldn't consider this an epic fantasy adventure that will be looked at by many as one of the great movies of our day. It does some minor things that I could pick at like the giants being oddly weak at the end, the beanstalk being too easy to chop down, and the score not being particularly strong and moving, but it a fun, family fantasy adventure that is worth you checking out. I am awarding Jack the Giant Slayer an 8 out of 10.