Pierre's was also my suggestion when you posted on the Mid-Atlantic board.
Note: Acc. to the way the Chowhound moderators have split the state between
two boards, :-( this is the more appropriate board for your question because Morristown/Florham Pk. are in Northern NJ.
Phone Pierre's Bistro and see what they can offer. Several years ago, we had a rehearsal dinner there and were extremely pleased. Food was excellent, the service was efficient and unobtrusive and the price was very fair (certainly not ultra high).
Our group also numbered about 30 so we opted for a private room, which kept us isolated from the very busy Friday night crowd.
There are numerous other restaurants in the Morristown/Florham Park area so hopefully others will chime in. As there is continual confusion about where central and north Jersey meet, you may also want to post your message on the Mid-Atlantic board.