The One With Ross's Wedding, part 2 - S4-E24
Audio problem: Toward the end of the episode Ross' Dad and Emily's dad are arguing. Ross comes between them and you can hear the audio saying"From now on everybody gets along!" But it does not match up with the movement of Ross' lips.
The One With Ross's Wedding, part 2 - S4-E24
Audio problem: When the wedding officiant says "take thee, Ross" his lips don't move. (00:20:35)
Answer: Usually by the seventh night of Hanukkah you don't know what to get the other person, and you will probably resort to getting the other person something insignificant. Chandler is basically saying that the pen is a stupid gift.