"Parenthood" is a 1.85:1 film, was shot for the 1.85:1 aspect ratio, and the 1.33:1 version would NOT be a complete 100% transfer of the full negative. Most, if not all full frame transfers of spherical films are always reframed somewhat to remove boom mikes, camera equipment and for compositional purposes. You can either call these titles pan-and-scan or MAR (Modified aspect ratio). It's just as incorrect as people saying full-frame transfers of Super 35 films are simply "removing the mattes."
An example of the exception to the above, of course, are some of Stanley Kubrick's films. Also I believe that Peter Weir has had some of his films transferred fully 100% open as well.
If you have the Terminator 2 UE disc, check out the Super 35 full frame/widescreen featurette on the disc. Spherical 1.85:1 films also use this system, as well as scope 2.40:1 films.
Again, don't blindly assume that a 1.85:1 or Super 35 film is simply "open matte" on disc.
Jason is basically right, except for the "if not all" part, as there are many other true open-matte films on home video other than Kubrick and Weir.
Other noted exceptions include some animated films, and lots of low-budget horror and other 'B' pictures, many of which are shot knowing that the vast majority of viewers will see them on video, even when there is a theatrical release. But there are other exceptions.
Parenthood is probably not 100% open-matte, but it might be.
The only way to know for sure is to compare versions, which is going to be hard without a film print.