A short game that is fun while it lasts...
The game is short, with only 13 missions that last about 15-30 minutes resulting in a total of 4-6 hours of gameplay. This isn't a big problem, as all levels are completely well designed and fun to complete. There are various enemies, all who fight differently and some are smarter than others. Enemies vary from Orcs, Uruk-Hai, giant spiders, Undead ghosts, Nazgul, Troll's and a lot of mini bosses who are quite tough to take down. The big boss fights are a lot of fun too.
The graphics are great in detail and the animations are good too. The characters look really good and life-like. The only thing lacking is facial animation, but this is only noticeable when they talk and their mouths don't move.
The worst thing about this game is the saving system. You can only save in between missions. There are some checkpoints throughout the missions but they are far and few. Basically, when you're by the end of the mission and die, you will have to start all the way from the checkpoint near the beginning.
There is also a leveling system. You earn experience points when you kill enemies and such. With these experience points you can purchase various useful abilities for your characters at the end of every mission. Experience points also unlock higher levels for your character allowing you to purchase better abilities. This is a nice feature, but you won't notice too much of a difference.
Now for the best thing: Coop.
Coop is great when playing with a friend, but if you have a PC I would recommend getting some kind of game-pad. Coop is good in many ways such as your friend "having your back" when things get a little overcrowded. Coop also makes objectives with time limits much easier and less frustrating, making the game even more fun.
All in all, Lord of The Rings: Return of The King is a solid, fun game that is worth playing. I recommend you try it, but it might not suit everyone's taste.