The home video of older home movies at the end has sounds of the children playing baseball, at the beach, etc. Home movie cameras of that era didn't have sound. Sound cameras came out very shortly before camcorders became readily available.
Andrew Beckett is called as a trial witness late in the plaintiff's case. This is totally incorrect as he would have been called to testify first as the plaintiff. That establishes his case early and also tries to force the defendants to give in and settle.
When on the witness stand, Walter Kenton says that, while in the Navy, he and his fellow Navy men dealt with an unethical Sailor by sticking his head in a latrine after ten of them had used it. "Latrine" is an army term. The Navy would use the word "head".
In the hospital scene, as Tom Hanks' character lays on the bed, an oxygen mask is a placed upon his face. The mask's strap is clearly caught under the mask; it's between the face and the mask. Later in the scene, the strap appears out from underneath the mask without being moved.
When Andy steps out of Joe's office (after Joe's rejection to become Andy's lawyer), you see him standing and reflecting on his situation. He turns his head to the left, and you can see the lining of a rubber mask on his neck(used to make Hanks' head look shaved).