If I'm not mistaken, Robert Zemeckis filmed much of his films (most notably the Back to the Future Trilogy) with the "full-screen"/"wide-screen" issue in mind. The "FS" version of the movies makes the transition well with most of the relevant action taking place in the center of the screen and the FS or the WS version simply adding extraneous and irrelevant information on top and bottom or the sides respectively.
I think the worst format is "Pan and Scan" which arguably FS more or less is when done to a WS movie. Ugh. Growing up my parents would always rent videotapes were pretty much universally 4:3 in the day for home viewing on a TV, though I suspect WS versions of select movies would have been available. Growing up I never minded this and like many diluted people was bugged by the "black bars" on the top and bottom of the screen when watching a WS movie. But when all you have is a 36" 4:3 TV playing a movie displayed in a very cinematic 2:1 format can be very troublesome.
Not long after getting into only watching things in OAR I saw a P&S version of a movie and the artificial camera movements in it became very obvious.
It's very different today, obviously and with 16:9 TVs becoming more popular the WS issue becomes a smaller one and more of an issue anymore is when films with a different AR are shown on a 16:9 TV.
But I will admit that I'm not a fan of watching 4:3 DVDs on my TV the black bars on either side of the TV are harder to take and, in fact, on my TV set to 4:3 they're gray bars.
The recent TNG "Next Level" Blu-Ray does offer black on either side (a bit less distracting to watch) and the various "stretching" settings on my player don't do well on the BD disc (The "smartly stretched" option isn't available that stretches the edges more than the center. Instead it's either a zoom or a stretch that stretches the entire picture evenly.) I suspect this is a function of either a limitation with Blu-Ray itself or the particular disc. The player has no problems doing the "smart stretch" for 4:3 DVDs.
In the end I say things should be presented in OAR and then the end-user can make the adjustments needed to "fill their screen" either by zooming or stretching the picture.