By you I mean the average Joe, who grew up watching Star Trek re-runs, not the guy in the klingon suit drinking romulan ale.
This been said, here we go:
Most people think Spock never smiles, and this is true for most episodes of the series. It seems his personality was built as the show went on.
But, in the early episodes, He is shown once in a while with a big smile on his face, as seen on the picture below, from season 1 episode 16, "The Cage".
