When Dexter pretends to call his parents, he actually calls T. I. M. - the speaking clock. In major cities people dialed 8081 to get the time from their land-line phone (or phone booth). It is still possible to do this in the UK by dialling 123.
People might think Dexter is being ungentlemanly by letting Emma walk nearest to the kerb but, later, when he gives her his number, it is shown that he is left handed so it is natural for his left hand to hold her right hand.