It’s frustrating to watch Disney’s increasingly mercenary tactics for wringing money out of its dutiful audience, which is already expressing outrage over the way Up (Buena Vista) is being released: The latest CGI film from hit factory Pixar (Toy Story, The Incredibles, Finding Nemo, etc.) is available on DVD in a standard-issue $20 disc or deluxe two-disc $30 edition (the extra $10 mostly gets you a digital copy to download onto portable media), but Blu-ray fans will have to cough up a whopping $45 for a four-disc edition. (Weirdly, one of those discs is just the film again, but on DVD.) With the holiday season approaching, Disney has to know that a lot of people will grumble but shell out: Up will no doubt be a highly sought-after Christmas present. The latest from Monsters, Inc. co-director Pete Docter and Nemo co-director Bob Peterson starts out with a heartbreaking character sketch as nuanced and sensitive as anything Pixar has ever done, then heads off into a crazy, unpredictable adventure. It’s a must-see, and even at $45, for a lot of people it’ll be a must-have…