We haven't quite covered every reply yet. I was about to mention the Alapin Gambit (3. Be3).

And as much as I like gambits, I never saw the appeal of the Milner-Barry Gambit in the French, though I do play the Caro Kann gambit with the same name.
I'll agree with the poster above who said that French players at low level see the Advance far more than anything else, so we end up being
really prepared for it. That was my experience when I started playing the French, rated around 1250 USCF at the time, and probably until hitting the 1500s or higher. As white, I'd recommend avoiding that variation at first, just for that reason.
The real question is whether the white player wants to really learn the French, or would prefer to focus on getting better at tactics. If your goal is tactical improvement, then go for the Exchange or Alapin Gambit, both of which pretty much give up the first move advantage, but give you wide open, tactical games where you'll learn tactics or die trying. Especially the Alapin, partially because of the lead in development gained from gambiting a pawn (the double edged nature of gambits), and partially because of the balanced and potentially boring pawn structure in the Exchange. Going with one of these would be my recommendation for a 1400, since learning tactics is more important than learning a specific opening at that level. Also, French players tend to hate the Exchange, and most of them at that low level won't have seen the Alapin before, so they'll have no clue how to deal with it.
If you really want to learn something about the French, then Nc3 and Nd2 are probably both good options.
I really don't understand all this fear of the Winawer for a 1400. It's not like he's going to walk into the mainline of the poisoned pawn facing opponents who know all the details as well as a GM. Just push 4. e5, unpin with 5. Bd2, and send your knight up to Nb5 to try and wreak havoc in black's position. Maybe it's not the strongest line to play by master standards, but it's sound enough, avoids the most demanding main lines, and can be fun to play. That's actually the line I was playing as white in the one and only game where I got a definitively winning position in a slow tourney game against a master... which I then proceeded to blunder away in time trouble and lose the game anyway. But that's why he's rated over 2200, and I peaked just short of 1800.