I believe they started protecting for widescreen during Season 4, but the correct aspect ratio for Buffy is and always will be 4:3 (excluding "Once More With Feeling").
I noticed on the back of season 3 in the store today that the back said "modified to fit my screen." Was it originally in widescreen, but modified for the DVD release?
Grab your stakes and holy water Jeff (Kleist), it's time to party once again.
Brandon,
you have it somewhat backwards, Buffy isn't protected for 16x9 (it's should be but isn't, lot's of follies visible in the dead space on the sides from what I understand), it's protected and composed for 4x3 within the 16x9 frame.
The shows intended (by Joss Whedon) ratio is 4x3 which is extracted from the 16x9 area, this is how the show was meant to be watched by Whedon and co.
I think we ought to figure this issue will never be resolved until we're talking about watching Buffy in high definition. At that point, I suppose they could windowbox the shows to 4:3, but they've already completed the HD masters in 16:9 so I doubt it. I mean, that's the whole point of even filming in 16:9, right? For when nobody's monitors will be 4:3 anymore?
When I attended a taping of The Drew Carey Show, all the in-studio monitors had 16:9 images with 4:3 markings and I DEFINITELY would not enjoy watching their compositions unless the aspect ratio issue was moot. If this is what Buffy would be like, I can wait.