Before appearing in this film, Robin Williams and Billy Crystal were already a well-known comedy duo, thanks to their work in Comic Relief. The original French film this is based on, The ComDads (1983) also features a well-known comedy team: Pierre Richard and Gérard Depardieu. Just the previous year, Williams and Crystal had appeared (though they shared no scenes) in Hamlet (1996), which also featured Depardieu.
When Dale and Jack are looking through the picture album, Dale starts to take a picture out of the book that's mostly dark (dark blue and gray) and Dale tells him not to. When they turn the page, that picture is mostly red.
When Dale and Jack are driving slowly over the bridge, an overhead shot shows a minivan behind them in the slow lane. When the camera shot changes to inside the car, a sedan is behind them.