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Did it look like a particularly old movie (in 4:3, for example)? It could be the Errol Flynn version.
Do not mess with creatures which you do not understand.Well, considering almost all movies were formatted to fit your screen during that time, yes, I believe it was in 4:3, but otherwise, even as a kid I had a good eye for film, and this one was definitely not an old movie, it was modern (for the early 90s that is). I'm also ruling out Prince of Thieves and Men in Tights, as I've checked the intros for both movies on YouTube and neither of them are it.
Well, there is a big bright sun in the opening of that version as well, but still not it.
To try to narrow it down, I looked at IM Db, and my guess might be the 1991 version with Patrick Bergin and Uma Thurman, although I can't seem to find a clip of its opening anywhere on You Tube (and a Google search comes up fruitless), so I can't confirm it.
It's free to see on Youtube. Opening is exactly as you described. https://www.youtube.com/watch?v=WpqrPTPXwrU

My sister grew up in the 80s, I grew up in the 90s, and our parents used VC Rs to make mix-tapes of various movies for us when we were growing up, either by (illegally) copying retail VHS copies we'd rent from the video store, or whenever they would air on cable TV. One tape as I recall included the Disney version of Robin Hood... except that before that, it appeared they mistakenly began recording an entirely different version, a live action version, and stopped the recording when they realized the mistake they made. As I recall, the opening title sequence for this live action version started off with quite a lovely wide shot of a big red sun either rising or setting on Nottingham before dissolving to a panning shot of a darkened Sherwood forest; the recording abruptly ended after a cut to a rabbit surveying its surroundings from the grass.
And no, I can't just check the tape and look at the names from the opening credits and check, because I was really young when that tape was made, as I believe it was one my sister took with her when she moved out.