Hungry hungry hippos is actually a really easy board game to make a movie of. Have it be an animated film about hippos going on an adventure. Either have them searching for food or one quick gag about being hungry and you've got HUNGRY HUNGRY HIPPOS.
Action Man? Eh, property name enticed me but I wouldn't want to jump on board. Doesn't seem to have anything to really play around with story wise, at least with hippos you can have some fun and make it clever (think Madagascar just with hippos as the protagonists).
They should create a Toy Cinematic Universe. The hippos can be genetically altered by the aliens from Battleship as a weapon to exact revenge against the humans. Action Man can be recruited to lead the war against the Hungry Hungry Hippos. The Biker Mice from Mars--ancestral enemies of the Battleship aliens--track their enemies to Earth. There they form an alliance with Action Man to defeat the Hungry Hungry Hippos.
An aftercredit scene can subtley tease Discord, ala Thanos from The Avengers.