The wine that Art opens in Kudrow's basement is Chateau Petrus from Pomerol (identifiable by the red seal at the bottom left corner of the label), probably the most expensive Bordeaux red wine, and contrary to what Art said in the movie, even young Petrus costs much more than $75 per bottle.
Actor Miko Hughes spent time with many autistic children at a special school. He also worked with a Chicago child psychologist to understand how to portray an autistic child.