There were these two guys from Israel who apparently never experienced childhoods and decided to make up for it by writing and directing a children's movie. You can tell immediately that they are totally clueless about children because their two main characters, 12 year-old Zach and 14 year-old Becky, are not just lifelong friends but are what passes for the movie's romantic interest. Any child and anyone who remembers their own childhood knows that at age 14 girls are two or three years ahead of boys. While you often find the reverse (age 14 girl with age 16 boy) this utterly absurd pairing immediately dooms "Lenny the Wonder Dog" for anyone over age six.
Basically what you have here is a very low budget version of "Agent Cody Banks" goes to "Police Academy" and meets "Mr. Ed". So low budget that the action scenes have been replaced with cartoons and the horse has been replaced with a dog that does not move his (or her) lips when talking-just a lame voice-over.
Throw in a couple of henchmen who could be described as "The Mayor of Munchkin City" and a male version of the mayor's secretary from "The Powerpuff Girls". Add a prestigious veteran actor, Officer Larvell Jones from "Police Academy" and a villain who looks and sounds like Al Pacino imitating the Tom Hanks character in "The Ladykillers".
If any of this sounds vaguely interesting, it is not. No one with an age or an IQ over six will find much entertainment here. Zach and Becky have some charm, but all the other characters are adults acting infantile, making this one of those kid's movie without any kids. Writers without childhoods must think that children get off watching adults act like cartoon characters rather than watching actors their own age.
There is a guest appearance by an Argentine pop singer named "Angie" (not Angie Aparo) who apparently was expected to become a big thing at the time of filming but whose US career seems to have suffered the same fate as this movie.