We called Ice Age: The Meltdown "an improvement on the original" but some critics gave this eco-minded toon a frosty reception. In the end, of course, it's academic and this story of cuddly critters battling the elements (voiced by the likes of Queen Latifah and John Leguizamo) raked in just under $200m. Given those numbers, don't expect this franchise to become extinct any time soon.

The Sub-Zero Heroes

If you invest in the two-disc version of Meltdown, you may be disappointed to find that it's mostly made up of throwaway featurettes. Some are barely over a minute, like Meet Crash And Eddie and/or Ellie, which cobble together soundbites from the producers with clips from the film. However, there is a playful element to the bonus disc that enhances the entertainment value. For instance Crash And Eddie perform three added stunts, like a game of basket ball with a ball of dung and there are mock news reports about the discovery of a prehistoric squirrel (Scrat) running rampage in the frozen wilderness.

John Leguizamo looks as though he's auditioning for a presenter slot on kids TV in Silly Sid. He shows how to achieve Sid's "lateral lisp" by sucking on lemons, munching on chocolate and stuffing his face with crackers. Then in Sloth Dancing To Sid's Sing-Along he invites us to cut the rug with some disco moves and make monkey noises. Sadly Leguizamo is not available for children's parties...

Breaking The Ice

A TV Special on the making of the film picks up the story so far and gives a quick overview of the varying stages of production. A couple of other featurettes go into more detail about character design and the modelling phase that precedes the CG animation process. Making A Scene focuses on about ten seconds of footage where Scrat falls into the sea and is attacked by piranhas. It combines two of the biggest challenges faced by the design team: animating fur and animating water. And don't even get them started on wet fur...

Elsewhere there are demo reels showing the early stages of animation and a Sound Effects Lab that sets the piranha scene to five differently themed tracks. Naturally one of them includes lots of farting and miscellaneous toilet sounds.

We're not sure about the educational value, but kids will probably lap up six mock educational films, ie scratchy monochrome animations each focusing on a creature from the Ice Age period. Leguizamo and co provide witty voiceover, introducing the vulture as "nature's garbage and music man" and the possum as "nature's spunky spectacles". Four games add some interactive fun.

If you opt for the single-disc edition, there's just one trivia game and the No Time For Nuts short film featuring Scrat. There are also two audio commentaries from behind-the-scenes folk who expand on the ways they sought to push the animation envelope and flesh out the characters introduced in the first movie.

While younger viewers will probably be content with just the film, the wink-wink humour on disc two will more likely appeal to older children. Either way, you're left with a warm yet eco-friendly glow.

EXTRA FEATURES

DISC ONE