By: Addison Wylie The fine people at Disney usually have a good handle on their films, which is why the occasional slip-up- like Planes or last year’s Cars 2 makes me more sad of its existence than angry at how bad it is. Planes, an animated film taking place in the Cars universe, plays like an undemanding direct-to-DVD time filler.  It’s funny that Planes comes out on DVD/Blu-ray a week after Blockbuster announced their final closings…