Assuming you're a foreigner required to take TOEFL in the first place, definitely retake. 100 is borderline (I recall some universities need a *minimum* of 100), and the last thing you want the admission officials or potential employers to think is that you're not capable of communicating effectively in English. If you can score 150+ in GRE verbal you should easily score better than 100 in TOEFL with better preparation.
