Let me start off answering this the way I did recently on a thread on Chowhound and here several weeks ago (in an essay on “hot new bistros) in saying “since there are no definitions or restrictions in the question, so I'll use Humpty Dumpty's rule here, [which boils down to] "When I use a word...."it means just what I choose it to mean — neither more nor less." So a bistro/bistrot is just what I say it is.
Here are some recommendations :
New - L'Apibo & Pantruche
Old - Chez L'Ami Jean pre-September 2012
Old still standing - Paul Bert, Repaire de Cartouche & Regalade
Old and new - 122 (The Bistrot d'hier et aujourd'hui)
Fish bistro - Bistro du Dome
Best new wave - Les Jalles or Volnay, L'Agape Substance
Best in tapas clothing - Flora
Best in cantine clothing - Cantine de Troquet Dupleix
Best in café clothing - Cartuche Café
Best according to Simon - Baratin
Best according to Pudlo and Lebey - Volnay.