Kew Gardens - Not bad at all!
We went down for our license and were in and out in less than 30 minutes. Contrary to what you were told, we were greeted by a helpful worker as soon as we walked in. She gave us our papers and checked on us a few times to make sure we were okay.
It was actually kind of neat - there were people down there waiting to be married, all dressed up in gowns and tuxes. Set the mood...
There is a municipal parking lot right behind the building for easy parking.
