Animated movies are usually pretty good but nothing that great to me. However, this one is a "keeper." It gets high marks for all the jokes in here, lots of which are adult-style but not sleazy or filled with sexual innuendos, although there are a few of those, enough to make this PG, not G. However, the vast amount of clever lines is the main attraction here.
Actually, the jokes come so hard and fast, it's hard to keep up with all of them. The visuals aren't gorgeous, as many modern-day animated films have become, but they are interesting. Not only is there a ton of gags to hear, but there are to see, too. You almost have to stop it frame-by-frame to see all the funny stuff penciled in the artwork.
The story couldn't be simpler but it manages you keep your attention and doesn't overstay it's welcome, although I think animated films are more effective it they don't go over 80 minutes. This one is closer to 90.
There is a good message in here, too. Maybe I'm mistaken but what I heard was the idea that just because people might be old, decaying and not as productive for society, it doesn't mean you have to discard them. Life has value and is precious from conception to dying of old age. Amen to that!