My not-quite-3 year old enjoyed it on several levels on the plane back from Japan a while back. I'm not sure she gleaned any particular message from it, but if you're asking in terms of action/violence/language concerns, Despicable Me is pretty tame stuff – almost all the really scary/painful looking stuff happens to vaguely-anthropomorphized yellow blobs.
At 5-6, it'd probably also make for an interesting plot that's also "easy enough" to have an extended conversation about, to help draw out themes, vocabulary, etc if you want to take things that way.
deano.com 
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