A previous reviewer 'corrected' someone by pointing out that all films in this collection are widescreen - this is not true! While 'A Bug's Life' can be flipped over for a widescreen version, Monsters Inc. is definitely 1.33:1 / 4:3, not widescreen, and there is only a single side to the disc. This was obviously very disappointing, and I cannot think of any reason why the widescreen version would not be included.
The specifications on the packaging confirm this ("Full Frame 1.33:1").
Will now have to shell out more for a proper version of this film. Buyers beware.