Freedom Force is an enjoyable, if brief, game suitable for all ages.
It's fun and simple enough for younger players to get right into - I didn't even need to look at the manual, since the opening mission/tutorial is quite comprehensive. Most pleasingly, there's no gore or even deaths, though naturally the game is built around violence, albeit comic-style.
Though the game itself is quite brief (as single-player, at least), it's entertaining enough. The story is quite engrossing, there's plenty of amusing moments (though it's not quite as funny as No One Lives Forever 2 or the Fallout games) and gameplay is straightforward and enjoyable, if a bit frustrating at times. There's some nice touches, such as having particular characters make comments on their current mission, even though you can choose from a wide number of them. Hence, you can go through the game again with different parties of heroes, and hear lines you wouldn't have without them. Characters are quite distinct and have a wide variety of powers, but I find that I rarely use them. I didn't touch an active defence once, and only stuck to melee attacks and the occasional ranged one.
The game is not without its faults. The voice acting is hard to judge considering the game is a spoof, but several times the tone and timing of delivery is simply wrong. In general, Mentor and Liberty Lad are particularly annoying, and Pan's followers are so irritating I had to turn the sound off. Characters are often very slow to react to enemies, and sometimes won't react at all. If you wind up with characters off the screen, much of your time will be spent pausing and switching over to them to ensure they aren't just standing there and getting pummelled. The game can become quite sluggish with many characters on the screen, and it's often hard to see characters when the scenery gets in the way.
Despite over 30 missions, it should only take a week or so to finish the game. Some missions can be quite tough, but with the grossly overpowered Supercollider character (so overpowered that it feels like cheating to use him, even though he was included with the game), anything can be beaten. I haven't tried the multiplayer component, but the single-player campaign is interesting enough to be worth getting the game for alone, especially now that it's gone classic.