You should go in Paris during summertime, too. It's amazing.
The fireworks at Eiffel when New Year comes. It's a delight to see.
And if you don't know French already, try to learn a few basic words (bonjour (salutation during the day), bonsoir (salutation when evening comes), au revoir (it's like saying bye), merci (thank you), oui (yes), non (no), s'il vous plaît (please), etc.). They really appreciate it.
Thanks for the tip, looking for a place to be for the fireworks!