I love terminal 1 if you can see past the layer of dust and grime it is a revolutionary architectual design. It's so 1960s Kubrick, Barbarella, The Jetsons and I think reflects the spirt and hope of jet travel from that time. It is easy to get about the terminal and everything is logically placed. I have never suffered the delays at terminal 1 that I have at terminal 2. That said, in what I perceive as a great tradition for French "grand travaux", it suffers from the "build it and forget it" syndrome. It has fallen into great disrepair and should have been renovated ages ago. Fortunately renovations have begun and it should be returned to its former glory in the next few years.
Terminal 2 is nice if you are in the newer Air France terminals that are very open and airy with the high uninterrupted ceiling and large glassed walls. The older terminal 2 buildings are similar in design but the checkin area is much smaller causing pedistrain flow problems and the inside of the terminal is more cluttered with small structures. They also are starting to show signs of "build it and forget it" as they are falling into disrepair and need a thorough cleaning which I would assume will not happen any time soon.